1: Professor Mannix Prewett
"the aged, serene, unjust (noun redacted) from a good family." (Yes, I'm maintaining my spoilers policy. Gotta have some secrets).
The Prewetts are a perfectly decent family by anyone's standards, which is saying something. Mannix is a variant of manach, "little monk."
2. Professor Bernard Baines
"The smart reporter with unexpected depths."
Dumbledore seems to be getting desperate. Baines is Welsh, nicely lacking particular resonances ("son of Einws") with the additional benefit of recalling another Baine with unexpected depths. That's only funny to me, but I don't care. I do what I want. Bernard from Germanic "bear + brave, hardy."
3. Professor Fulton Abney
"The poised, stingy, bullying politician."
This jerk wants 'practical experience' before joining the Department of Magical Education... if there is such a thing. I suppose someone needs to check that the homeschooled witches and wizards are actually getting schooling. Abney from d'Aubigne, dating to Hastings and the Magna Carta; Fulton from Old English "bird-catcher's town." Trying to be obnoxiously English. (Success?)
4. Professor Charlotte Knaggs
"The awkward, pompous smuggler with a dark past."
This one should be fun. One of Dumbledore's charity redemption cases. Charlotte because "Lottie" appeals, and Knaggs is used in Yorkshire.
5. Professor Appius Osborn
"The enduring tomb-robber."
Infamous in his profession but lacking investors for his next venture due to increasing disruptions from the war. Appius from the Roman praenomen used by the clan Claudia, and by the guy who built the Aqua Appia and the Appian way. Osborn from Old English "god + bear" mixed with Norse cognate.
6. Professor Edna Oliver
I fancy having an ex-Auror who lost
7. Professor Kenneth Seward
"The tireless, unethical exorcist."
This one's going to have a hell of a time at Hogwarts. Cognate from Irish "handsome" or "born by fire"; "descendant of Stuart (protector of victory)". Sounds decently self-righteous :)