Checkout the Github repo of osy86 who managed to get TB3 of NUC8i7HVK working under macOS in a way a real Mac does, by flashing a firmware from Apple to the thunderbolt controller of that NUC.
https://osy.gitbook.io/hac-mini-guide/details/thunderbolt-3-fix-part-3
https://github.com/osy86/HaC-Mini