It's a bit confusing to me as the cosmetics are on IMX but they also have some stuff on L1. I think you can earn gold zbux (tokens) only if you own a weapon pack (L1). And green zbux (in game currency) if you are f2p. There's definitely more to it than that though, but it was hard to find too much info yet since it is still kinda early.
I know one of the modes you'll only be able to use whatever weapon packs you own but the normal modes I guess you can always use all the guns, and the NFTs are just cosmetics.