GreXXL unfortunately my Formulaire extension doesn't allow for "random" users to edit a user profile, as it would be pretty chaotic. Only the user themselves and moderators can edit a profile. There is no concept of submissions within a user profile, but this could be a new feature where I create a new kind of form where you can have a submissions about a user, and then somehow make the submissions public on the profile page.
Right now I am planning to introduce a user selection field as a new field type. This is meant as a standalone feature but could open the door to new features where submissions are selected or aggregated by the value of that field.
Though if the goal is to create a "classic" feedback system where there is some validation as to who can review who and some sort of aggregate score and leaderboards, a custom extension would probably be a lot more practical instead of repurposing something that was meant to create profile fields originally.