You're not likely to hear Hozier and Ariana Grande talked about in the same sentence. They're two very different sides of the same coin and certainly attract entirely different audiences.
That being said, when you're Hozier and you want to mix things up, the best possible way would be to throw people off with a totally jamtastic cover of Ariana Grande's "Problem".
A few months ago Hozier covered "Problem" in BBC Radio 1's Live Lounge. Seemingly, Hozier might have an attachment to that particular cover because 6 months later he is still performing it live.
Thousands were at the festival to witness the live performance and, judging by the crowd's response, Hozier might have to make a permanent space for "Problem" during his live set.