>>43643442...ah, nevermind what I said here, I was looking up her scenes and some Japanese wepages, and I think I completely misinterpreted what was going on.
The "shakiin" bit is her trying to sound really cool, but she immediately realizes how stupid it sounded and spends the rest of her pre-battle dialogue stuttering and sounding really embarrassed. It's cute.
The English translation of her HGSS dialogue just ignored all the stuttering, does she do it in the Masters translation?