"Anyone know what style Art these .jpgs are called ?"

They basically look hand painted in a 2D program, but since filters do that automatically, it's not always easy to tell what was done by hand and what was done in auto-mode.

The only program that springs to mind when I see those pictures is "Corel Painter", because Corel Painter lets you do both, you can auto-apply a custom paint effect and you can also paint over an image (using a custom paint style) and do it manually.  So for example, you might tell it to do oil painting, and then go over parts of it manually if you think it looks too uniform.  You can design your own paint styles as well.

Or, you might like the output of a style but wish it had more of a scruffy edge here and there, or that it had used a different colour, so you can change all that manually after it did the auto-paint (or at any time before, during, and after).

But yup, Corel Painter is the biggie if you want that sort of thing and want to paint over it manually as well, it's regarded as the best for that sort of painting but it's not cheap.  They used to do a cheaper version but I've not seen a new release for the cheaper version for years.