Support Off-angle
A support player taking an angle away from the main formation to add a crossfire sightline while forcing the enemy to split dive attention.
When a support stands on an off-angle, it adds one more crossfire sightline, and the enemy has to watch the support on the flank while looking forward. At the same time it puts them outside immediate peel from the team, so the premise is being able to keep the spot "expensive" with an escape route and cover (walls / corners). Unlike a DPS off-angle, it is a high-difficulty operation that has to combine survival with keeping the healing sightline, so it usually falls to heroes who can put out damage while healing (Ana / Bap / Zen and the like). You have to constantly weigh the sightline value of the off-angle against the cost of the peel you give up, judging moment to moment whether right now is a situation to step out in.
When the enemy is committed forward and there is no dive on the supports — Ana / Bap / Zen and the like adding a sightline from an angle. Only works while you are on a position with LOS breaks and an escape route, since peel will not arrive in time.
Taking a dive at a spot peel cannot reach and dying there, so the team is down a support. Or stepping out to the off-angle cuts the healing sightline and the tank fighting on main dies with no heals.
Off-angle
Solo position offset 60–120° from the main formation, enabling crossfire while taking minimal return fire.
Crossfire
Two or more shooters hitting the same target from divergent angles so no single piece of cover blocks both.
High Ground
Elevated map position offering downward sightlines, cover, and safe retreat — the foundation of most setups.
Peel
Switching mid-fight focus to protect a backline ally from a diving threat.
Concentrating heals and boosts on one ally to give them a structural advantage in their duel.