TUN with Teltonika TRB140 Router

[Bambos]

Hello Everyone,
i'm using site to site Open VPN with shared key between pfSense devices.

Now i'm trying to implement the same with a Teltonika 4G Router as Open VPN Client and pfSense as Open VPN Server.

I have trouble matching Teltonika client options in comparison to pfSense menu and options.

For shared key, Authentication: "Static Key" key selection gives the following menu. (i assume is the correct because TLS authentication needs also certificate authority , client certificate and client key)

What settings do i have to put on pfsense server side ?
on pfsense there is more options like negotiation , auth digest, fallback etc...
can you see any matching settings with Teltonika menu ?

Any input much appreciated. Thank you.