Here are my Best-Rated One True Pair-Ups:
Tank (If 6v6 is Reimplemented or on Open Queue):
Pint-Sized Mech Pilots of Overwatch M.E.K.A. and the Unofficial Hamster Junker Champ: D.Va and Wrecking Ball.
Forged Alliance of Talon and Null Sector Leaderships: Doomfist and Ramattra.
Sharp and Prickly Marauders of The Phreaks and Junkers: Hazard and Junker Queen.
Subordinate Talon Brute Squad: Mauga and Sigma.
The Overwatch Rival Defender of Numbani and Crusader: Orisa and Reinhardt.
The Pure Overwatch Muscle Strength Between Gorilla and Superhuman: Winston and Zarya.
Roadhog is Wildcard for Now Until the Next Tank Hero.
Damage:
Long-Ranged Deadlock Gang and Talon Rival Femme Fatales: Ashe and Widowmaker.
The Ironclad Guild Binary Relationship between Human Dwarf Master and Omnic Servant: Bastion and Torbjorn.
The Overwatch Air Force between the Aviator and Her Robotic Wingwoman: Echo and Pharah.
The Mid-Ranged Ex-Overwatch and Shimada Mercenaries: Freja and Hanzo.
The Speedsters of Overwatch: Genji and Tracer.
The Demolitionist Derby of the Ex-Junker and Wayfinders Society: Junkrat and Venture.
The Genius Overwatch and Vishkar Minds That Think Alike: Mei and Symmetra.
Talon’s Deathly Deceivers: Reaper and Sombra.
Overwatch’s Elderly Rapid Shooters: Sojourn and Soldier: 76.
Cassidy is a Wildcard for now until the Next Damage Hero.
Support:
Overwatch’s Secret Biological Weapons: Ana and Mercy.
The Peace and Tranquility Between Human Warrior and Omnic Monk: Aqua and Zenyatta.
Talon and Vishkar’s Renegades of Biological Warfare: Baptiste and Lifeweaver.
The Absolute Inti Warrior and Overwatch Thrillriders of South America: Illari and Lucio.
The Female Youngsters of Project Red Promise and the Yokai: Juno and Kiriko.
Brigitte and Moira are Wildcards for Now Until the Next Support Heroes.