Watch movies from Time Capsule on Apple TV
Yes, but you just need a client that is able to play your video files.
I'm not sure which Apple TV generation you use, but if it's 4th gen you can download an app called "Infuse 4" https://firecore.com/infuse

If you use an older generation you can use another solution by the same vendor (I don't have any experience with it) https://firecore.com/atvflash-black.

This guide mentions how to connect to your Time Capsule:
https://support.firecore.com/hc/en-us/articles/215090977-Streaming-From-Other-Devices