I am planning on upgrading my NAS to a new motherboard sometime in the next few months. I have almost everything ready and just need to order the parts once I have a bit more money, but there is one thing I am still unsure of. The local IP of my server (192.168.0.XXX) is used to reference my Cloudflare tunnel and a bunch of my docker apps use it, like plex. I have a cox gateway router (not my decision) and want to know how I could set the local ip of the new machine to the old machine's ip, so I don't have to change all my network settings for everything that uses the old address. What would be the best way to do this? Is there a way to set a static local up in Unraid settings? Or would it be best to access the admin portal of the router after transferring the usb and all the drives?

You could set it up as a static IP in network settings. Also use IP reservation in your router so it assigns your server the same IP everytime while leaving it set as dynamic.