not gonna lie, it's pretty bad. But with a little work, you could do well. Nightmare Zero is one of my favorite villains and a series like this looks interesting.
1. The characters are far too small. You need to resize the characters to match the backgrounds you used.
2. Mixing handdrawn effects and sprited effects looks horrible. Try to stick to sprited effects
3. The text boxes are too small and disappear too fast. They also look horrible. Since it's megaman x, they should be at the bottom of the screen or top to fit the style. This was the biggest problem with the movie.
4. Be careful mixing styles of sprites. You have to have an eye for it. I hope there's a purpose for the Megaman Zero sprites being there. Usually style mixing is okay sometimes if you know how to mix the styles right.
5. The movement is horrible. It's extremely choppy and unnatural.
6. The story needs work. People seemed to randomly show up, with no explanation. "dr. light brought me back"? That was awful attempt and explaining. try to put some real thought into it. try to use some plot to develop the characters.
Fix this stuff and you could make this series pretty awesome. I will be watching you.