I didn't want make a so long and serious talk on a similar matter - I know that of course it's ridicolous something of this kind xD - I wanted just be a little more clear why some people can see the two characters different, nothing more.
Everyone is free to like who wishes, of course =)
Phase 4's jp voice does sound good deepened. Kasumi's jp voice (and Kokoro's and Marie's and Honoka's etc) sounds like a squeak toy when she gets hit which is why I keep the eng voices on
The difference is really little but is there, the face of Kasumi and Phase are not created using the same polygons. Phase seem to miss some of them for a final outcome more rounded compared to the original character that has a face more elongated (shapened wasn't the right term, sorry for the misunderstanding).
How do I tell Kasumi and Phase 4 apart? Easy. One farts out cherry blossoms and the other farts out green smoke. Also, Kasumi has more brightly colored outfits, while Phase 4 has darker colored outfits. Oh, and I just read the names under the life bar. Lmao
Lol, ok I will provide two completely exact picture next time, so maybe I will convince you xD (by the way it's true that an open mouth alterate the face, what a silly mistake for me to make a comparison with a such example xD)