Ideally I'm looking for something similar to the ubiquiti edgerouter lineup
-Nice metal chassis, plastic still ok
-at least 1GB RAM
-decent amount of eMMC storage.
My goal is to run openwrt with a good amount of addons like Wireguard, AGH, DDclient, etc. My home internet is 600/600 fiber. I currently have a Fortigate 80E I got from work after a client upgraded. It's overkill but works well. My goal is to just consolidate all these things into one device and looks like openwrt can do that.
There’s GL-MT2500 that almost meets all your requirements: https://www.gl-inet.com/products/gl-mt2500/. Currently OpenWrt snapshot only, but will be stable sooner or later. It’s wifi sibling GL-MT3000 is already on stable.
It won’t be able run Wireguard faster than ~355 Mbps. Probably less with other software you want to put on.
I have the AX3000 (beryl AX) travel router already. I think the wireguard speed is based off decryption not encryption (host vs client) though I could be wrong. I like where your head is, but maybe a little underpowered for a home firewall.
I've got to pile on with the first couple of responses, x86 is how I'd go.
The x86 is unbrickable, has more core Linux testing than all other arches put together and typical mini PCs these days are cheap, expandable, efficient. I got one of the N5105 ones with 4x I226v (2.5 GbE), about 15 months ago. Plopped in an 8GB SODIMM and a 256 GB SSD, off to the races. Total expenditure was about US$200, because I bought the RAM and SSD new (both of which are waaay overkill for this application). It has been running 24/7 since I got it, no issues, consumes 8.8w on average.
The newer N100-based boxes can be had for less now than I paid for the old N5105, grab a ram stick and ssd salvaged from a laptop and you can probably do the whole thing for sub $150. Power numbers are lower for the new devices, too, I think I recall someone here testing an N100 at sub-6 watts after messing with some sysctl settings (could have been over on STH, hard to keep track on a thread with 2000 posts... https://forums.servethehome.com/index.php?threads/cwwk-topton-nxxx-quad-nic-router.39685/)
The R5C has 4GB/32GB memory/eMMC, 2.5G ports. The CPU is enough for 600/600 ISP and everything else you've listed. If eMMC and budget are important, it's a good choice.
The R4S lacks eMMC and has just 1 GB ports, but the CPU is a bit faster. The R4SE has eMMC if you can find one, but it is not officially supported by OpenWrt.
But if you search for "n100 2.5G" on AliExpress, etc. you'll find plenty of low power fanless x86 options for little more cost. I too think you'd be better off with one of these unless the compact NanoPi solves a limited space or budget problem for you.