Yes to the first question! Just make sure to elaborate that the item will be changed in the description of the canon update.

As for the magic rule, don't worry about being super specific like that in terms of the semantics. As long as the magic is just one power itself, you can add specifics about how the power works and any limitations/caveats as an additional explanation. TL;DR you can have teleportation and have him lose his clothes or keep them, it's up to you!