I configured a Lookup, but the display order of the fields on the Record Selection screen is not in accordance with the Lookup settings
If the field specified as "Key Field" is not included in "Fields Shown in Lookup Picker," the field is displayed in the leftmost column on the Record Selection screen.
If you want to display the field specified as "Key Field" in any column other than the leftmost column, you first need to include the field in "Fields Shown in Lookup Picker" and then configure the display order.