Heucheras, (as long as there is some bright light or a bit of sun occasionally) Lamium maculatum, Geranium maccorhizum, Campanula muralis Tiarella

Vinca minor - there are white, mauve and purple flowered ones, some with double flowere. There's one which has variegated leaves, too. This plant spreads - so you wouldn't need too many!

Yes, it spreads, Spritz, but I never think its good ground cover - far too straggly and open for that purpose.

Sorry - I was adding to your list...I have the double one which grows between other plants, as ground cover. It looks lovely. The variegated one also scrambles about in a corner I can't get to, and that's useful, too.

I think I'm biased, I've had to deal with too many that have spread all over the place over the years, lol. Another for the list - Tellima grandiflora

Ajugas are great for this kind of situation, too. I'm the proud owner of a PINK flowered one now! :-)) I do like the variegated leaved ones.