I'd really examine your motive here to be honest

Do you want to be funny? What's probably going to happen is people are going to want to engage in conflict with you and think you're despicable, so it probably won't be funny. If being funny only for you and a couple of your friends and unpleasant for everyone else works, that's fine.

Do you want to convert people to communism? Again, this is more likely to be read as "look at this, a communist is being argumentative and worshiping le evil red fash, I hate that and I hate communism". There's a reason it's a pipeline, of the many people I have ever converted I have never not even once mentioned Stalin to any of them within the first six months of discussion, except to cede ground that he wasn't perfect and fucked a lot of things up.

Do you want to engage in conflict for the sake of conflict? Probably a good fashion choice then. In that case, there's not really any point in learning any of the history or rebuttals, because they're going to see that the same way you see defending Hitler. Your best bet in this case is to just be prepared to meet abrasion with abrasion.

Do you want to wear it because it's your shirt and you like it and it makes you happy? Sure, 100% valid. Be prepared to engage in conflict and have rapport shut down before it begins, but don't let that stop you from living your truth.