When you add a new instrument you've a choice between "common instruments" and "all instruments" for example.
Or enter when you add a new instrument "guitar" in the search field. There you'll find the 12 string guitar too.
If you're looking for tabulator add a classical guitar (tabulator), select a staff, click right on staff properties. There you can customize the staff for your needs.
Comments
Yes, Musescore can.
When you add a new instrument you've a choice between "common instruments" and "all instruments" for example.
Or enter when you add a new instrument "guitar" in the search field. There you'll find the 12 string guitar too.
If you're looking for tabulator add a classical guitar (tabulator), select a staff, click right on staff properties. There you can customize the staff for your needs.
Or misunderstood I something?