I've seen two guides posted to Medium about animation in the last month that have seriously blown up!
- Taras Skytskyi's The ultimate guide to proper use of animation in UX
- Jonas Naimark's Motion design doesn’t have to be hard
There is a lot to learn in each one! The demonstration animations they use are wonderfully well done and each guide demonstrates an interesting and effective animation technique, often paired next to a less successful technique to drive the point home. They are both heavily focused on Material Design though, which is fine, but I think Val Head said it best:
Google wrote material design for branding Google things. When you use material design on things that aren’t Google, you’re kind of using Google’s branding on a thing that is not Google, and that’s weird. Material design is Google’s opinion on motion. It’s Google’s branding opinion on motion. It’s not a de facto standard of how motion should happen.