So I would say it depends a bit on where you are planning this tour...
In Europe where I have mostly toured, it can be different from country to country. In Sweden where I live, it’s legal to camp basically anywhere outside of built up areas, even on private land, but in most of Europe it’s technically illegal but if you’re stealthy, and stay off private land, it’s fine.
Back in the day, I slept openly on beaches even in the South of France and Southern California, but times they have been a changin’ ✌️