Picklists in Canvas Campaign Fields > Custom Fields

Hello! :-)

We are using the "ABC" picklist under the campaign fields > custom fields. Currently there are 2 values there. The values from that field is send to OSC when synced. The piclist "ABC" is used also in some forms so it has dependencies. I have to add 5 more values to the campaign field but if I edit the piclist "ABC" the new 5 values will be also visible in the forms (I do not want that).

The question is "can I create a NEW picklist that would contain also the 2 original values and the 5 new values & swap the picklists" ? "would it affect any OSC sync or already active campaigns?" The 2 values that might be in use by the active campaigns will be included in the NEW picklist :)