With the deprecation of UNet, support only extends to Unity 2018.4. This asset can now be upgraded (for $1 since free wasn't an option) to the new asset Simple Network Sync.
This is an add-on to the free Network Sync Transform (NST) project. Adds the ability to sync basic mecanim parameters of networked objects when using the NST.
Replaces the HLAPI NetworkAnimator when using Network Sync Transform, as the NetworkAnimator does not buffer frames, which will result in out of sync (early) animations when used with the Network Sync Transform.
NST Animator Add-on is integrated with the Network Sync Transform, keeping the Animator always in sync with the root movement.
Includes options for reduce floats to half floats, and options to interpolate floats and ints.
Try the free Network Sync Transform asset first and see if it is right for your project. You may then expand the functionality using the exposed callbacks and classes on your own, or by purchasing add-ons like this one on the Asset Store.