"Global" List (Float)? Assume I have a content type with a  list field (float) that can contain the following values: a, b, c.
I created three nodes (A, B, C) with those field values.

Creating a new node, is there a way to auto clear/remove already existing values in older nodes?

For example, if I choose a in a new node, I want that in node A that value is removed.

The Unique Field module does the job of preventing duplicated values, but it doesn't allow to remove values from other nodes.
I found a solution: use a field group (Field Group) of booleans and set them as exclusive values (Exclusive value).