Check out Clonezilla, which is the perfect tool for the job.

I am pretty happy with a Dynalink WRX36 Wifi 6 AX3600 router which has a 2.5 Gbps capable WAN port and 4 * 1 Gbps ports for LAN. I replaced the vendor firmware with OpenWRT which is working well nowadays, you just have to follow the install instructions closely. It can be had for $79.