My RB choices:
1. Pavard. Young, fairly priced as not many clubs are interested (after the world cup his price will sky rocket)
2. Cancelo. Good offensively, defensively he needs to work but can improve. good relations with valencia
3. Sidibe. Strong both defensively and offensively. bit older but he is a solid signing.
4. Odriozola. Young great potential to explode. Made the spain team over many other great fullbacks