I’ve been using two Rachio controllers (one Gen 2, one Gen 3) in Greece without any issues. The only change was the use of 220v power supply. They work like a charm.
Only recent hickup is the Alexa Skill. It is only available on the US marketplace. Used it for a bit through that marketplace and it worked like a charm. Soon after other EU apps needed the EU marketplace so I had to switch and the Rachio skill disappeared.
If it was also made available on the amazon.co.uk marketplace then that would be awesome.
I’ve noted previous posts of no plans to sell Rachio in Europe. Why not? The only thing I had to replace was the power supply. This is the easiest amendment ever. If the device comes with a 110v- 240v power supply it will be universally compatible out of the box.