music video animation/exporting transparent layer to premiere

Hey all! I'm trying to figure out the most efficient/effective way to create an animated (mostly frame by frame) layer(s) and have it match an existing music video.

I've imported the mp4 of the vid from premiere into animate (unfortunately, it's over 16,00 frames, so I get an error when I try to publish and see my progress), That aside, I'm having trouble figuring out how to export my animation layer(s) with a transparent background in a format that can be imported back into premiere, and onto a layer there that would enable me to check my work. it's basically lasers shooting out of the eyes of the singer whenever he's on the screen. 60 fps, so i don't wanna draw too much without knowing exactly what I'm getting into. Any help is great. Thanks!!

I tried animating this in after effects, but without an onion skin feature, my drawings were too inconsistent.