This grower is fairly sure of this plant identification.
They look more like Palace Purple than any of the others pictured. Lovely ground cover in the shade.
Heuchera micrantha ‘Palace Purple’ (Alum root). This variety has large serrated or jagged copper bronze leaves about 12 to 16 cm across. The flowers are panicles of green to cream flowers with red anthers.
Foliage, ornamental, borders, walls, rock garden, banks, under shrubs
Italics = data drawn from parent genus or speciesView Full Plant Finder Record