That seems to be a growing trend in Japanese fighting games, nitroplus, arcana heart, and koihime enbu do it as well, I don't really mind it
Basically you have to choose from a list of phrases if you want to talk. You cannot type "GG" or anything in the text box. So you have to awkwardly look for what you want to say. It feels weird but some of the stuff there is hilarious though lol.