A simple oil painting generator I created in Substance 3D Designer and rendered in Marmoset Toolbag 4 using Megascan plants.
The generator uses a Bitmap photo as input and adds several layers of brush strokes of different sizes that follow the main contours of the photo as closely as possible. You can easily control the size of the brush strokes and the level of detail you want. This makes it possible to obtain a very coarse or much finer result just by modifying a couple parameters.