The Smearframe Slack channel is an animation chat group where you can talk about anything from inspiration, tips, rigs and more. Get an invite from the link above and join the fun!
Tea Time Animation is a website and forum run by Lana Bachynski (Blizzard) that has a bunch of great advice and resources for animators.
Animstate Forum is filled with some amazing industry veterans and also has a lot of other resources across the rest of the website.
Polycount is a forum to showcase your work and recieve feedback, join in on animation challenges or just have a chat!