In SuperCollider 3.13.0, for receiving OSC messages, simply using OSCdef seems to handle OSC Type Tags "T", "F", and "N" correctly.
When sending, I don't know if there is an easy way like sendtyped in Pure Data (if anyone knows, please let me know).
see also about Pure Data (Purr Data):
https://gist.github.com/cleemy-desu-wayo/9d314e448b9f0edffcb2ffa503c3e824