The animation wasn't bad, but the action was pretty boring. Megaman is so OP and just blasts through a shitton of basic zombies (speaking of which, their size is inconsistent and it's a pretty lazy-looking way to use their assets, because WHY ARE THEY HUGE!?). He uses different moves, but there are so many times where he just mows them down without them coming even close. *He never gets attacked, except by the boss.* That's not a fight. On top of that, he's never actually hurt. There's no danger. The space is inconsistent, too, why did he go to the street in the lawn area to teleport to a random roof? The zombies just pop out of nowhere and get yeeted off screen immediately, occasionally with quick, hard to follow cuts. Then there's a mini-montage of all things in the desert that ends as abruptly as it started where he just gets random powers and blasts through everything. Even the big boss is basically useless. The problem is he doesn't work for the powers, he doesn't put in effort. That's why it's not compelling watching him fight. Different zombie types are underutilized and often pretty useless, like the Zamboni one at the start and the balloon ones. The football, pogo and digging zombies did something, but even they were a little too easy. There's just no strategy to it, he just gets more and more powerful.
Try taking this into consideration to make your next movies more interesting.