It's officially available to stream on Spotify, TK UN-APEX (English version), a short version as in the anime edit. It's basically like the original anime edit instead of a full version that you get for anime theme songs but with TK singing in English.
I think it's a first for TK? I just took a look at it recently (in my opinion, it wasn't promoted enough through official channels which is where fans check mostly) and not sure what to think. I'm not sure if I should be applauding this perhaps a lot of US listeners are? but to be honest I'm used to and like TK singing in Japanese. What language TK sings in doesn't matter to me nor should it matter to other people. I'll be interesting to see what TK does next. But one thing is certain TK can sing in English if he wants.
Listen to TK UN-APEX (English version): Spotify