When experiencing art slumps/blocks, I try to keep the creative juices flowing by doing repaint/redraw challenges, where the artist takes a scene from a show/movie/game or a classical art piece and reimagines it in their Owen style or in a different way.
I used this opportunity to experiment with different styles and hone in on my own personal illustration style. It also helped to gain back some inspiration for my own original projects that had fallen by the way side.