Install on an EU RE200 which has the TP-LINK US image flashed

It is possible to bring an RE200 in an invalid state where the EU hardware has a US firmware flashed.
The RE200 V1 is flashed by using this tool as recommended by the docs:

Now this only works with the older offical firmware RE200(US)_V1_171205 from 2018 (the 2021 does nto work). If you are using the latest offical US firmware, then you might get a verification failure in the UI tool or the flashing fails with error 18005 error.

So your RE200 is not bricked if you install the US version. But you can not use the latests offical firmware to create the flashing image.

Unfortunately, TP-Link sometimes uses different partition tables on different regions - this is very prominent (and problematic) in the WPA863x series. By carefully examining and creating intermediate firmwares it is possible to get it back to the correct region - but chances are high that it's getting bricked. I did so on a WPA863P where I accidentally flashed a US firmware on a EU unit.

Interesting! So in this case going back to EU was not really needed. I wonder though what happens if I would go back to stock EU.

I'm happy with openwrt now as the TP-Link firmware had weird bugs with DHCP.