In the case you rely on the strongSwan IPSec-based VPN solution then please have a look at the following package request: https://dev.getsol.us/T5016
I already submitted two patches to include the strongSwan and NetworkManager-Strongswan package in Solus which are currently under review. Nevertheless, you could use these patches now to build your own versions of those packages and install it. If you need help to do that then I would be happy to help you.
jman strongSwan supports secure IKEv2 EAP user authentication and authentication based on X.509 certificates or preshared keys. Please try it out!