With requiem installed (you need to use Quilt instead of Fabric), summon a shell with /requiem shell create. The game will crash as openpac attempts to treat the shell as an actual player. I think the way you're detecting players is flawed, though I can't be sure as I'm not familiar with the code base.

Can you post the crash report?

crash-2023-01-08_17.42.16-server.txt

Thanks!

After looking at the crash myself it looks like ladysnake.requiem.common.entity.PlayerShellEntity extends from baritone.api.fakeplayer.FakeServerPlayerEntity which probably extends from Player.

A possible fix for Xaero
Maybe detect all accounts - then get their player - instead of getting all player entities.

thanks for fixing it so quickly!