1.) If you want to sublimate on acrylic you need to buy special acrylic coated on the back for sublimation. This is not that common and the printing is not opaque, it's kind of translucent. The example you sent it not sublimation.
2.) To do what you're showing in the example you need a flatbed UV printer to print directly on the plexiglass.
3.)Alternatively you can print on clear vinyl with a solvent printer and mount it to the back of the plexi as well as adding a layer of white vinyl behind it.
Option 2 is probably the best way but likely the most expensive.
Option 3 works really well and can be done with more inexpensive printers but is more labor intensive.
