In my experience, the only real aggressive fish I have kept is a Flowerhorn. Always aggressive, couldn't walk by the tank without him rushing the glass. Always bit or tried when doing tank maintenance. When I initially got him, I had him in a 55 with an oscar and a vieja. all three were close in size about 5". The flowerhorn hopped the divider once and beat up the oscar pretty bad (the oscar and vieja shared one half of the 55). He was alone after that.
Kept a Texas that was very timid, a midas that was interactive but never noticed aggression (was killed by either the Texas, the labs, the vieja or the JD, never found out which), yellow labs both timid, two timid Vieja melanura (although one ate a hole into my injured oscar even after living together fine for months), a JD who is a bully with my vieja but never actually bites or injures (tank mates for almost two years now). All of these fish are or were afraid of me anytime im doing something in the tank. I have thrown in guppies with all of these fish as feeders and they end up being part of the tank except for the flowerhorn. Only the flowerhorn never allowed any other living creature in his tank.
would love a Dovii or Umbee.