"Although it's carrying its baby in a pouch on its belly, Kangaskhan is swift on its feet. It intimidates its opponents with quick jabs."​
- Pokémon Sword Pokédex Entry

Cards

Trading Card Game

Cards from the official Trading Card game. Click one to see the full scan and view info about each card.

Other

The back of the card displays a Pokédex entry, the Pokémon's appearance rate in Pokémon Red, Blue, and Green, and the details of the attack that's being used in the artwork. Kangaskhan here is using Dizzy Punch!
1997 Carddass Card

Manufacturer: Bandai
Origin: Japan

Carddass is the name of Bandai's card vending machines, the name of which is inspired by the AMeDAS, or Automated Meterological Data Acquisition System, and the idea behind the cards from these machines is that one can get data from them. The classic Pokémon Carddass series features some old and unique Sugimori art, and in each illustration the Pokémon is performing an attack.
1998 Sealdass Card

Manufacturer: Bandai
Origin: Japan

Similar to the Carddass cards, but this later series had stickers on the front. Stickers are called 'seals' in Japan, hence seal-dass. The back of the card shows some Pokédex data and the level-up moves Kangaskhan learns in Gen 1.
1998 Playing Card

Manufacturer: Nintendo
Origin: Japan

In 1998 Nintendo manufactured a series of playing cards featuring artwork of the Pokémon Stadium models on the face cards and aces. There were four decks total, one for each of the gen 1 Gameboy games, and each deck featured different Pokémon. This card is from the Green deck. A complete deck with the box is worth a pretty penny!
~1998-2002 Meiji Milk Chocolate Cards

Manufacturer: Nintendo
Origin: Japan

The first card is a lenticular card that shifts left to right. I believe this card was available as part of a promotion with Meiji Chocolates, a Japanese confectionary brand that has done a lot of Pokémon promotions (including the metal coins in the Miscellaneous section). Some of these sets feature a rock/paper/scissors aspect, some of them don't.
I can only guess at the blue card, I think it's also a Meiji card because it appears to have the rock/paper/scissors thing going on, and it's around the same size.
1999 Monopoly Professor Oak Card

Manufacturer: Parker Brothers
Origin: United States

From the original 1999 Pokémon Collector's Edition of the classic board game, published by Parker Brothers. In this version, the Professor Oak deck is the "Chance" cards.
1999 Lunchables Card

Manufacturer: Oscar Meyer Foods
Origin: United States

One man's trash is another man's treasure! One of my very first experiences with Pokémon was cutting out the little cards on Lunchables boxes and trading them with my classmates in kindergarten, and I know that's true for many other fans my age too. Having this brings back a lot of happy memories!
1999 Burger King Card

Manufacturer: Burger King
Origin: United States

These cards were included with Burger King kids meals as part of the iconic Pokémon: The First  Movie toy promotion. They came in an assortment that would tear apart with perforated edges. Each of the original 151 had a card, and the backs had 1 of 10 possible "movie scenes".
2000 Topps Trading Cards

Manufacturer: Topps
Origin: United States

Early on, Topps manufactured trading cards featuring artwork and characters from the anime. Kangaskhan was one of the 72 cards in Series 2. Each of those cards had two foil versions, silver and rainbow, and each booster pack had one random foil card inside. The foil I have is the rainbow version!
~2005 Bromide Card

Manufacturer: Ensky
Origin: Japan

Bromide cards are sold in packs of chewing gum. They're quite large and thick, and there's a lot of them. Since the back says "Advanced Generation", I assume these are circa Gen 3, but I don't know the precise year.
2013 Hanafuda Card

Manufacturer: The Pokémon Company International
Origin: Japan

 Hanafuda, or "flower cards", is a style of Japanese playing cards that has been around since the 1800s. A hanafuda deck has 48 cards: each suit features a different flower, represents a month of the year, and has 4 cards. When Nintendo was founded in 1889, it was actually focused on handmade hanafuda! In November of 2013, to celebrate Pokémon's 15th anniversary, the Pokémon hanafuda deck was sold in limited quantities in Pokémon Centers, and they purportedly sold out in 15 minutes! There was also other merchandise with the artwork of the cards, such as hand towels to metal buttons. Kangaskhan is featured in one of the two kasu, or plain cards, of the cherry blossom suit, which represents the month of March. Isn't it lovely?
2019 My151 Postcard

Manufacturer: The Pokémon Company International
Origin: Japan

One of several postcards produced for the My151 campaign. I really love this artwork!
2020? DKV Collections Card

Manufacturer: DKV Collections
Origin: Peru

Colecciones DKV is a Peruvian publishing house which sells flat collectibles (cards, pogs, etc) for various anime properties and Warner Bros characters.  There are YouTube videos from Spanish collectors of their Pokémon DKV Collections cards, but none I could find are from before 2020, so that's the only date I can go off of. They no longer have any Pokémon products on their website, so the legitimacy of these is a bit questionable. This set included a bunch of Shiny Pokémon and even Crystal Onix, so that's pretty interesting.
Newspaper clippings?

Manufacturer: Unknown
Origin: Japan

These are printed on a very thin paper reminiscent of color newsprint or magazine paper. The reverse side is some unrelated Japanese text, and the front side reads something like "Let's learn with Pokémon!" and features a word, its definition, and relates it to Kangaskhan somehow. The first clipping is for the word "nurture", and the second is for... something that translates directly to "tiger cub" and apparently means to fiercely protect something. Like a Kangaskhan protects its baby!
Mystery Flats
I've got no idea what these things are. One is from a Spanish speaking country and the others are from Japan, but that's all I can tell you. The square ones are very tiny, the other two have nothing on the back, and the Spanish one is about half the size of a TCG card. If you know anything about these please contact me!

Stickers

Amada Stickers

Manufacturer: Amada Publishing Co.
Origin: Japan

From 1996 to 2005, Amada published the majority of collectible Pokémon stickers in Japan. The stats on the front and back seem to constitute some sort of game you'd play with them, but I have no idea what the rules are.
1996 Retsuden Hyper Sticker Collection 1 #115
1997 Retsuden Hyper Sticker Collection 2 #318
1998 Retsuden Hyper Sticker Attack Set #53 - Fissure
1998 Retsuden Hyper Sticker Attack Set #185 - Dizzy Punch
1999 DX Gold #D111
2000 Hyper Sticker Collection 3 #532
2004 ??? #439
2005 ??? #790

Other Stickers

~1998 Batt-Memo Sticker Sheet

Manufacturer: Tomy
Origin: Japan

I believe these stickers were included to be used with the little Batt-Memo books associated with the Battle Coin game. See the Miscellaneous section for more info.
1998 Official Nintendo Player's Guide Sticker

Manufacturer: Nintendo of America
Origin: United States

This sticker is from the 1998 Official Nintendo Player's Guide for Pokémon Red and Blue, published under the  Nintendo Power brand. In between the walkthrough and Pokédex sections was a big sticker page that had stickers of each Pokémon in the game.
1999 Artbox Sticker

Manufacturer: Artbox
Origin: United States

Part of the Pokémon Sticker series 1 by Artbox. It had 232 stickers total: one for each of the original 150 (sans Mew), and a bunch of foil and bonus stickers with anime screenshots and stuff on them.
2005 Merlin Sticker

Manufacturer: Topps Europe Ltd.
Origin:  United Kingdom?
2012 Sticker Book Sticker

Manufacturer: The Pokémon Company International
Origin:  United States
2005 Bandai Sticker

Manufacturer: Bandai
Origin:  Japan

This sticker came with the 2005 Kangaskhan Bandai Kid.
2009 Bandai Sticker

Manufacturer: Bandai
Origin:  Japan

This sticker came with the 2009 Kangaskhan Bandai Kid.
Pokémon Pan Stickers

Manufacturer: Daiichi Pan
Origin:  Japan

Pokémon Pan (pan being the French word for Bread) is a snack sold in Japanese 7-11 stores. Packaged individually, these bread snacks come in many flavors and include a sticker, which has a distinctive texture and that little round bubble sticker with the Pokémon's name.

Other

1996 Pokémon Batomen Disc

Manufacturer: Tomy
Origin:  Japan

This is an accessory for a toy called Cyclone 2 (distributed by Tiger Electronics in the US, and as far as I know, there was no Cyclone 1), which used something called the "C. Code system" to read a circular barcode on the back of the discs and carry out some sort of battle game. There were many different series in Japan, and they weren't exclusively Pokémon, though there were several Pokémon sets. Cyclone 2s seemed to be a more generic thing in Japan and were blue (you can see a picture of one on the back of the booster pack, in the top left corner), while the American variant is Pokédex Red, and only the Pokémon stuff made it stateside. Anyway, the Kangaskhan Batomen was part of the Red series, and each booster had a handful of discs in it.