Has anyone tried either making NFTs or repurposing another game's NFTs in an open source game?

Repurposing would be a good way to get users interested. You could even use NFTs from a variety of games.Also, with the game being open source, I feel like the longevity of the game can be extended which would extended the value/life of the NFT.

One of my concerns is that with an open source game it would make it easier for someone to hack the game to show that they have assets that they really don't own. I'm not a game dev, but was curious if there ways of preventing this. Also, any other thoughts on the matter?

PS: If the feedback is "NFTs are worthless" without any reasoning as to why - really need not respond.