The best way to build motion graphics into prototype

I’m looking for a way to build a one pager that has animations as you scroll down the page. Initially I was using After Effects to show client and Dev how it needs to work. However I found Figmotion and it somewhat does what I need it to do albeit it’s going to take a long time to do this frame by frame. Does anyone know of or use a better method? An example would be this website.