Here are some web links to the work of other stencil artists. Most of these artists are working on very large scales and specifically on outdoor public buildings and structures.
I have not seen any artists using plexiglass as the stencil material; many are using paper, some type of board, or mylar.
https://www.stencilartprize.com/about/previous-winners/
https://mymodernmet.com/stencil-art/