Using version 23.2.4, I exported the settings from one Mac machine and imported the settings to a different Mac machine using the same DBVis version.
Everything seems to import fine except for the tab colors and borders.
I did restart the app several times.
I had everything checked when I exported and imported.
I have tested this and it looks as if the "Color and Border" settings set under Tool Properties->Database are not applied to the corresponding database connections after import. The settings themselves are imported though, so that when a new connection of the corresponding type is created, it will get the chosen color and border settings. Also, any color and border choices made in the connection are preserved.