Arantza Sestayo is a Spanish painter and illustrator who works promarily in the genres of fantasy and imaginative realism.
Her highly refined paintings and drawngs show the influence of Victorian painting, Art Nouveau and the Pre-Raphaelites. (Her image above, bottom, may be a nod to J. W. Waterhouse’s depiction of jealous Circe.)
Sestayo applies her skills across several mediums. If you scroll down on the home page of her website, you will find categories that translate as “Oils, Watercolor, Pencil, Comic, Sketches and Digital”. There is also a section featuring her book cover illustrations.
A number of her pieces are illustrations for a deluxe limited edition of Alice’s Adventures in Wonderland from Easton Press.
You can find several videos of her process on YouTube.
Art Renewal, also here and here