"The Hospital Morning"

Each rendered in Eevee. Took about a minute to render at 8K, so I could get as much detail of the brush strokes as I could. Baking done with Cycles. Brush strokes are instantiated, rotated, sized and colored using color attributes and geometry nodes:

Although I am really proud of how my solution turned out, I’d recommend something like Live Paint Filter that’s more real-time and even less changes to the scene in terms of workflow. The biggest advantage of mine is that I could tweak colors and stroke sizes directly, which helped me manage detail levels and Cycles noise.