If we're talking about fighting in Novel/writing, then I would recommend reading Re:Zero and Vivy: Fluorite Eye's Song.
Both were written by Tappei Nagatsuki and his attention to detail in every scenario is amazing, fighting included of course.
Re:Zero is rather more in-depth and technical in the fighting than people would imagine.
In season 1 anime (Arc 1,2,3), There's "Reinhardt vs Elsa", "Rem vs Mabeast", "Julius vs Subaru (arrogant Subaru getting bullied)", "Rem vs Witch Cultists", "the battle against whale", "Wilhelm vs Theresia flashbacks", "Emilia vs Betelguese", "Julius vs Betguese".
In season 2 anime - part 1 (arc 4), there's only "Beatrice vs Elsa", altough it's a good one.
And in Season 2 anime - part 2 (arc 4), there's "Garfield vs Elsa", "Ram & Puck vs Roswaal", and "Subaru & Beatrice vs Great Rabbit".
theres also Arc 5, in which everyone is fighting, That even the support character that usually didn't fight is now fighting in this arc.
theres also Arc 6, where the quality of the story is at peak. There's also fighting of swordman MC against the greatest swordman of the past, and Subaru finally became the best MC.
then the Arc 7, which happen in Vollachia, the land of wolves where strength is everything and all that matters. And Subaru must navigate his way through all the fighting.
then the arc 7 is continued in arc 8 (current arc), because all the fighting in arc 7 is taking too long and it needed to be continued in the next part.
And then,
if the usual MC Subaru is frustrating, then you can read the Re:Zero EX novels, which shows you the prologue of Rezero during the Demihuman war.
Of course, there's lots of fight in the war, whether its on the scene or off the scene and behind the scene, Its war after all. the MC's were the standard Fantasy resident that may look typical but have lots of originality into them.
and about Vivy: Fluorite Eye's Song,
i haven't watch or read, but i can see the quality fighting scenes just by looking at the trailer.
Thanks for reading this if you don't skim.