Asari duelist Melee is broken in multiplayer?

Hi, iv been playing her, after reaching lvl 20 on my vanguard, started playing her, and i cant shake the feeling that her melee is just so unrelayable and flat out broken, dozens of times iv fallen from the map when her melee teleported me to the edge of the platform, even when i try to reform a 0 distance melee it still teleports me around like crazy... vanguard can spam his melee all the time, her melee got teleport and a huge delay, you cant click it twice, theres a hidden global cooldown. i cant even finish enemies with her melee because it sometimes simply doesnt connect with my target. am i doing something wrong or is she bugged?
Description says shes a close range assassin with a sword, how can i assassinate anyone when her melee doesnt always land?
Is it only me? or is she not meant to be improved vanguard altogether? is she a gunner despite what the description says?
thanks for help.

heres her gameplay video if you dont know: