I think you need to be more specific, One Piece and The Gamer are two VERY different things. Have you seen this before and can't find it now or are you looking for something like if One Piece and the Gamer crossed over?
I think that's already too specific if you mean a literal crossover between the two. I'd say try TheGamer subreddit, and make a post there. It would be easier to find sifting through the smaller work, because One Piece works have ended up covering pretty much everything.
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