SmartCard Support for Openvpn (pkcs11)

Anyone been able to use a pkcs11 module with openvpn acting as a client on their device?
I have the MUDI and have a client connection back to my main network through openvpn, i would like the cert/key to reside on a device such as yubikey nano such that the private key is protected in case the device is lost/stolen.

This is the closest i have found to what you want:

For PKCS11 and files i have not seen how to do it.