It's a really, really bad idea. I'm Hindu so, the swastika actually has religious importance to me, but I go above and beyond to avoid displaying it IN THE U.S. even.

I wouldn't wear/display it outside of the temple or my home, and only use it during the puja itself.

If you had some strong religious argument for why you ABSOLUTELY felt that you could not practice your religion without having a swastika on your person for some reason, even then I would advise you to conceal it.

Having it on a cool T-shirt is not a compelling reason. Please don't.

Please stay safe. I don't want to see you on locked-up abroad because you couldn't resist an edgy shirt, lol.