adobe animate assets

Adobe stock has some, but not a lot. 

Since Animate is way past its zenith and its community is fractured and almost dead, the introduction of the Assets panel did not result in the enthusiastic creation of a market place, where people like you could find endless supply of animated assets.

As far as I know such a place does not exist and no one has any interest or motivation to create Animate assets.

You may be able to find old Flash files from the bygone era when Flash ruled the world.