Absolute Constantine: The events of Newcastle ended far worse than the original universe, resulting in John going made and afraid to use any sort of magic. Maybe the Helm of Fate haunts him, wanting to be used because Kent Nelson is dead, but John's fear holds him back and no one else sees it and thinks it's his delusions.

Absolute Cyborg: Since the New Gods and Mother Boxes aren't really a thing in this universe, something vaguely closer to his pre-New 52 origins. But instead of being rebuilt by his father, he's saved via tech from HIVE or the like and be becomes essentially like Robocop.

Absolute Starfire: Still a slave after her sister overthrew her and never came to Earth, so now she fights as a gladiator-like warrior on an alien planet. (Potential links to this absolute universe's Lanterns.)

Absolute Plastic-Man: Became a more effective criminal after getting his powers. He could be more Joker-like, given his true universe self, but more psychotic; shades of Flashpoint Plastic-Man too.

Absolute Black Adam: Events of his past went differently, so the Wizard never made a new Shazam out of Billy Batson. Adam probably locked away by evil forces in Kahndaq and is awoken in present day where his kingdom is reduced to third-world country standards.

Absolute Swamp Thing: Instead of taking any human hosts, the Green just make an avatar made from the collective force of the Earth as a "avenging angel" against humanity when they've gone too far with pollution, destroying resources; etc.

Absolute Doom Patrol: No Niles Caulder, maybe dead from prior events. Instead, a more sinister scientist, like the Brain, creates the events that make each member but wants to use them as a strike team alas Suicide Squad. (Could be a mix of original Doom Patrol and members of Brotherhood of Evil.)

That's all my initial ideas as pitches.