Welcome to the BOARDS!
Sounds like a great trip, I won't be in europe until the end of July though,
Boo. Shoes are a tricky part, I decided on bring a pair of Nike sandals (had them forever and I know they can take the wear 'n tear) and a pair of sturdy hike shoes. They're beige in colour so I think they'll blend into whatever. :D
Just remember you'll need something with support for all that walking on different terrain! If you have doubts for the colour, but go with something neutral. Dirt will just blend in and it should match with everything!
Have a great trip!!!!