I' always search for E80 styles, my e50 has only 120 styles bur E80 much more, all plenty compatible on e50/60.
How i can get it?
Simpy copy it from E80 factory data at http://www.rolandus.com/uploads/CMS/Downloads/2033/E_80FactoryData.zip

Enjoy all e-80 styles

can you play e-80 music styles on a e-50?
how do you do it?

Yes perfectly, e-50 e-60 and e-80 uses some soundbanks, some sequencer , some styles format, the only difference is that e-80 has about 20 sounds more and some sound is stereo sampled.
Symply put the styles on a floppy-disk or in interal memory of your e-50 end play e-80 styles