Frame wrasse is my favor...

From my experience both, I watch them pick at other fish in stores all the time, I've also witnessed a few kill other fish.
Really depends on each fish though.

For a while there was posts every couple of weeks from different members asking how to catch the 6lines and get them out of their tanks due to aggresion. I know several people including myself that used to have them and no longer do cuz they ended up killing other fish. They're one of my favourite fish, really active and cool colors but they're evil. Always the same story, "but mine is so well behaved" few months later another post is up by same poster looking for a trap.

Adding any fish at this point is iffy..it will probably get chased.

Ya it kind of surprised me everyone saying there so aggressive. I thought that it was the 8 lines that were bad. From researching on the net. But it does say there not compatible with some other wrasses. Once I get my new tank up and running ill be looking to add a new one and if I see any aggression at that point they'll get banished to the frag tank ( but I want a wrasse in there anyway to eat any bugs)