Lol are they really going to randomly acquire super powers in this movie

Well, I mean most of them randomly acquired their powers in the gamea too. At least a good amount of them do, like Liu Kang'a fireballs or Kung Lao's teleports. Even ones that are canonically established like Sub-zero's ice or Johnny Cage's green energy were basically explained as magic or sorcery.

Establishing that spiritual energy exists and can be manifested as special abilities is actually a pretty good way to go about it. It allows characters to have their signature moves from the games but doesn't make it seem completely random.

That being said, I still think some characters should have technology to stand in or enhance their arcana. For example, Kano's laser should come from his bionic eye, although maybe his arcana could help him focus it.