I tried all types of stickers and glue-on lenses, some lasted a few dives, others were lost on the first splash.
There are many brands that have some models in which you can replace the lenses with corrective ones (takes a couple of minutes), or order them pre-installed if buyinga new mask.
Me and wife both use some Mares x-vision variants, and we just replaced the lenses to +2. It is just like reading lenses only at the bottom of the mask lens, to watch gauges and focus camera, and of course the little critters too.
If you opt for a mask with lenses, better check a model that fits your face, but in in my opinion it is the best solution.
You may not need +2.5, as the water/air refraction index difference already magnifies by ~33%