Trying to understand your idea, so you want to build cross-chain protocol layer. So something like OpenSea but support more chains or something like NFT game with cross chain support, maybe like Enjin whom founders co-authored ERC-1155. Maybe peak into NFT projects on different chains and you may find a way how to combine more NFT projects into one and create perfect solution for your ideas 
Edit: I think this proposal extends your ideas data-wise Minimalistic on-chain cross-game NFT attributes