Where I live (western Virginia) the prevailing term has always been Scotch Irish, with or without a hyphen; the same for the states of WV, KY, TN, and NC — the states south of the Potomac. North of the Potomac, the prevailing terms are Ulster Scots and Scots-Irish. Everyone thinks the term they use is the right one, so I get corrected no matter what :>( . . . I simply use the term that is traditional here.
That’s weird. I live in soutern North Carolina and always read and hear Scots-Irish. Oh well, it shows to go you.
Don’t forget ‘revenooers’.