Fun fact, Apollo is the only major Greek God who doesn't have another name in Roman mythology. (For example, Posedion is Neptune in Rome).
Perhaps that will come to play during his fight somehow?
Prediction for remaining humans volunds:
Leonidas-Spear or Armor.
Qin Shi Huang - Terracotta Army or these:
Tesla - I think his volund will allow him to create shit in the middle of combat, or something to do with electricity, but idk lol. Sky's the limit for him.
Hayha- Obviously a sniper rifle lol.
Kintoki - In the legends about him, it appears he didn't use any weapon. Idk I think a club would work for him,
Souji Okita - He was seen using a sword, but I'm not 100% if that will be his volund. It likely will tho, if I had to wager.
Nostradamus - ???? I want him to start pimp slapping mfs with a book lol, but I have no real idea tbh.
Rasputin - Idk why, but I think it will be a cross. Just cause it would look dope aesthetically.