One of the most striking features that distinguish Scots from English is the treatment of Old English /o?/ (guid /g?d, gød, gwid/ “good”, muin /m?n, møn, min/ “moon”, guiss /g?s, gøs, gis/ “goose”) and /u?/ (hous /hus/ [hys] “house”, mou /mu/ [my?] “mouth”, nou /nu/ [ny?] “now”).
However, this is a feature Scots shares with Northern English dialects (J.C. Well, Accents of English 1, pp.185f):
North of a line running from southern Cumbria to the Humber estuary, the present-day dialectal reflex of Middle English /o?/ is a front vowel, e.g., [g??s] goose, while Middle English /u?/ remains monophthongal, e.g. [hu?s] house. […] It Scots dialects, too, the back vowels were exempt from the Great Vowel Shift. It seems that what happened north of this Lune-Humber line was that Middle English /o?/ had become fronted to /ø?/ some two centuries before the Great Vowel Shift took place. This meant that in these dialects there was no half-close back /o?/ to raise and thus push the close /u?/ aside into diphtongality in the way it did elsewhere (and /e?/ did to /i?/ everywhere) when the Great Vowel Shift came into operation.
In other words, with regard to these two groups of words, the Northern English dialects could also be regarded as Southern Scots dialects. If Scotland had always remained independent and had managed to incorporate this part of England, they would probably now be writing “guiss” and pronouncing it [g??s], and there would be some pressure to drop the schwa and say [g?s], instead of replacing it with [gu?s], as I’m sure is happening at the moment.
Of course these dialects aren’t like Scots in all regards. For instance, I believe their reflex of Old English /a?/ isn’t /e/ or similar like in Scots (where we get hame /hem/ “home”, gait /get/ “goat”, hale /hel/ “whole”), but something more similar to standard English /??/.
I don’t know much about these dialects, so I’m not sure whether they share many more features with English than with Scots, or whether they really are equidistant from both.