ISP Router change in my HomeLab

cross-posted from: https://lemmy.world/post/12521221

Dear all, I have some questions for what I'm about to do with my HomeLab. I recently upgraded my connection to a 1000/1000 and the ISP sent me this shit ass router (Fastweb Nexxt) which is very locked down. I want to change it.

Today this Fastweb Nexxt is not doing DHCP because I'm running a VM with OPNSense on it from which I manage IP reservation etc.

The fiber connection comes to my house and it's connected to a small box, an ONT from ZTE. Then an ethernet cable goes to the wan port of the Fastweb Nexxt and then LAN to my server where the OPNSense VM is hosted.

Now, I'm open to solution, the goal is to remove the Fastweb Nexxt.

The "Cheap" idea would be to use a USBC to Ethernet cable so to add a second Ethernet card to my server and connect the ZTE device to it. I would then assign in OPNSense this cable as WAN and leave the existing card as LAN for the switch. I'm quite sure I would need as well to clone the MAC address of the Fastweb Nexxt device and assign this MAC to the wan of my OPNSense right?

I'm open to any kind of suggestion, even something like "this is the best home-router for 100€"