From Nattasha, Pierre and the Great Comet of 1812
Moscow: 3 singers, amazing song with strong vocals, upbeat
Sonya & Nattasha: 2 singers, another great song, slower, dramatic
You could do stuff from Wicked, but please don't for the sake of humanity
But what I think you should really do is choose a song that all of you love and portion it up. 4 is an awkward number and this would be the easiest way to get around it. Suggestions if you do that:
Meadowlark or Chanson from The Baker's Wife
Burn from Hamilton
Good luck, let us know what you choose.
I appoligise for any spelling mistakes. I may be on my mobile. Clumsy fingers and small little touchscreen keys don't mixx. I try to spellcheck, but I may miss something.