Can We bridge metadata via POS bridge in the case of ERC721?

No, because ERC721 Predicate doesn't handle depositData to have anything else other than tokenId or tokenIds., but Using FxPortal Bridge the users can easily pass any metadata along the deposit function and the FxPortal smart contract properly handles the encoded metadata throughout the entire operation and successfully transmit it to the user child token, in the child token we can then receive this metadata in bytes while the token is being minted and then setTokenUri accordingly after decoding the metadata.Also it can be done with ERC 721 via base uri/getting uri on fly with token id. Moreover, users can go with ERC1155 in the POS bridge.