@Nebbie
 
Yeah, that green goop wasn’t there before (looking at the video), so you appear to be right.
 
That was, in fact, basically bug blood dripping from a tree branch, far as we can tell.
 
Also, the wording of “they’re gone?” Probably meant to convey “dead.”
 
_{In any case, I always did like to think Starlight is willing to kill something/someone in self-defense, post-reform.}

@AC97  
There’s green goop that appears after the magic, which is probably melted flash bee flesh and hemolymph. I think Fluttershy would understand.

I wonder how Fluttershy would react to this? Would she be sad, but understanding? Would she be angry at first? Or would she be more frustrated with Trixie?
 
There’s technically nothing to say the Flash Bees died… but I’d imagine it’d be rather hard to focus on that many at once to teleport them, or something, especially when they’re trying to electrocute you, and either way, she was firing magic at them, which is generally not what TPs look like.
 
She didn’t really have much of a choice.