Is it possible to change the field type of a relation field?

For several setRelation fields, I would prefer not to utilize the standard searchable combo box.
How can I alter the type of the field (or column) to allow it to be used as a standard CHAR field so I can quick search freely and also have those advanced filter options (see img below)?

image

In contrast to the default options (for relational fields):

image

Thx in advance.