more specific: can I use jwt .net implementation to create a token and use jwt node.js implementation to verify the token?
The implementation details does not affect to the format or content of JWT, so you can perfectly use .net (A) to generate and node.js (B)to verify.
For B to be able to verify the token, use a RSA asymmetric key pair, public and private. A signs with the private key and B verifiew with the public.
It would be possible to share a HMAC symmetric key between A and B. But then it is needed to consider the security issues of having the key in both systems and how to synchronize them.