Hi, fellow first time novelist! I'm just about to cross the 70,000 word mark on my first novel, which has some fantasy elements and action scenes as well.
I don't know how good my advice will be, as I've not taking a writing class since my freshmen essay writing workshop at NYU almost ten years ago, and as this is the first time I've attempted to write a story longer than a 200 word early reader picture book, but I can at least off my method, in hopes that you could pull something from it. When I write action I watch it in my head first, like watching a movie. You might even want to watch a few well-shot action sequences in films and take note of what the director does: when does he use wide shots? When does he use character POV? Enemy POV? etc.
The following is just opinion, and is very general since I obviously have not read your specific text, so take it as just some general guidelines. I would definitely avoid writing out the action sequence in its entirety from each character's perspective, unless you are specifically trying to make a point about how their perspectives vary. Otherwise readers will be bored reading the same scene three times over, especially when the pacing of your writing should be at its quickest to move the action forward and to promote a sense of urgency. Either choose one character through whom we can experience the scene or, if you are writing in a true third person and thus can switch between perspectives, then write pieces of the fight from each of their view points and weave them together to form the complete scene.