Yes, it is feasible to update US firmware to an EU device.
Yes, it is feasible to update US firmware to an EU device.
Check if you can switch the firmware on your Archer A6 (v2) from EU to US. The EU version is likely no longer supported, but the US version remains functional. For US firmwares: https://www.tp-link.com/us/support/downl.../#Firmware EU firmwares: https://www.tp-link.com/de/support/downl.../#Firmware
I wouldn't recommend it. TP-Link sometimes stores calibration data in the firmware chip, so if these two firmware versions aren't identical, you might permanently lose the information needed for 5G performance. In fact, I think their different firmware comes from varying WiFi regulations. It could work less efficiently, or you might end up broadcasting illegally.