Luffy ok, but Loki could be in his prime.
He was above Harald even before the fruit and years ago.
Loki could definitely be in his prime, but I would find it hilarious, if Loki‘s haki, niddhorg form, his human form and Ragnir are that strong, that he would not achieved his hybrid form. Or he may also have hybrid form, but not awakening.
it would make sense that Imu would overwhelm them both, before Luffy is mastering more and more his G5 (again 5 min plus he couldn‘t kill Sommers..) and Loki awakening his DF, even if I‘ve no idea how his awakening would be we don‘t even know his hybrid