Detach a Mirror Column

I don’t know if this option already exists, but I would like to detatch a mirror column and keep the column’s category and values.
For example, I have a board called “Architecture Projects”. On this board I am mirroring the land address of another board: “Land”.
I need the addresses to be a location column and not a mirror column on the “Architecture Projects” board.
There are +400 items and it would be a lot of work if I had to retype them all.
It would be very easy if there was a button to “unlink” a column but without losing its category and values