More identifications for public reference, in case this is helpful to anyone down the line.
Feel free to send me anything for ID.
@Julius19 sent photos of the following (which are the first photos in each section):
1999 Nagatanien Nakayashi Walkie-Talkie Giveaway Campaign Raffle Sticker
1999 Nagatanien Nakayashi Walkie-Talkie Giveaway Campaign Raffle Sticker
永谷園のなかやしトランシーバープレゼントキャンペーンの応募シール
Original Product: Nagatanien Sushi Taro (4 servings)
すし太郎4人前
I referenced a similar Mew copy here:
The back provides a lot of useful information.
This is a sticker that is used to participate in a raffle to win a Nakayashi Walkie-Talkie.
The deadline for the raffle is also listed on the back, which (in this Mew’s case) is November 30th, 1999. Dates in Japan are sometimes written using the Japanese era name, so it states Heisei 11 (平成11年), which is 1999. Some of the other cards state Heisei 12 (平成12年), but this Mew has the closest appearance to your card. You can look at the back of your card too see when the deadline for the raffle is, which will give you a better idea of when your card was produced.
It also states that this product was from a package of Sushi Taro すし太郎4人前. All of the cards above in these links list this as the originating product.
Your copy is peeled already (bottom) and says “please try again!”.
Image of Walkie-Talkie from Yahoo Auctions:
Source: 【非売品】なかよしトランシーバー ポケモン 永谷園|Yahoo!フリマ(旧PayPayフリマ)
2010 Top Pokemon Diamond and Pearl Nameplate Gum
2010 Top Pokemon Diamond and Pearl Nameplate Gum
2010 トップ製菓 ポケットモンスターダイヤモンド&パール ネームプレートガム
According to this website, came with “two cards and a nameplate”.
Pictures of the packaging:
Pictures of the contents (exact match for your set):
1998 (?) Mirinda Pokémon Food Cards
1998 (?) Mirinda Pokémon Food Cards
美年达 神奇宝贝 食品卡
(I am unsure if this promotion ever had an official Chinese title, but those search terms on Chinese search engines such as Baidu will pull up those cards, especially in image search).
Released with a Mirinda promotion in Mainland China. The characters used are in Simplified Chinese. “Mewtwo” in Taiwan would be 超夢 (as opposed to 超梦, which is what is on your card). “Pokémon” in Taiwan would be 神奇寶貝 (as opposed to 神奇宝贝, which is what is on your card). “Pokémon” in Hong Kong would use the Cantonese spelling.
Here are some pictures I grabbed off of Chinese auction sites. It includes your Mewtwo, as well as many other Generation I Pokémon:
2005 Pokémon Center Holon Tower Sticker - Mewtwo Vs. Rayquaza
2005 Pokémon Center Holon Tower Sticker - Mewtwo Vs. Rayquaza
2005 ポケモンセンター ホロンの研究塔 シール
BGS states the source as Pokémon Center - Fanatics Collect
I do not have data on distribution for this specific sticker for Holon Tower. However, in 2007, a similar sticker for the TCG set DP Shining Darkness was distributed “…at the Japanese Pokemon Centers, back in 2007, if you purchased more than 3000 yen (about $35) worth of items during a special limited time campaign.” This may be a similar case. I no longer trust this source as it misidentified the Pokémon Diamond and Pearl Ramune Stickers (The Giant Pokémon non-TCG Identification Thread - #247 by sableguy) as a Pokémon Center promotion instead. My apologies.
(Quote from: Pokemon Center 2007 DP3 Shining Darkness Darkrai Mew Absol & Friends Sticker NOT SOLD IN STORES)