I looked before, there's another post that says it's not posible to trade between japanese and non-japanese and the same question for GEN 3, but what about other languages? I'm talking between my spanish yellow and english red
The original generation 1 Pokemon games can trade with each other as long as they are both legitimate non-Japanese releases. As for trading between a Japanese release and non-Japanese release, your game's save file will be corrupted. Only Japanese releases can trade with other Japanese releases in gen 1. Hope this helps! :D
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