Use logic, feats, and stats.
Assume firepower and shields are equalized.
The First Order has StarKiller.
The Covenant have High Charity.
The galaxy's are merged. Covenant on one side, First Oder at the other.
Both at their peaks.
Well
Covenant:
Ground Troops-
Hunters(tough, without knowledge of weakness very hard to kill)
Grunts(also they can repopulate like crazy)
Those flying insects(annoying, repair ships)
Elites(invisible, strong, energy swords)
Brutes( huge, very tough, can smell targets)
Jackals(very agile, good eyesight)
Equipment:
Wraiths
Halo reach Revenants
Ghost
Choppers
Shade turrets(plasma and heavier rounds)
Banshees
Seraphs
Those U shaped ships
Drops pods?
Plasma grenades can stick
Brute grenades can stick and throw spikes on explosion( I believe)
Power ups:
Bubble shield
Invisibility
Over shield?
Hologram?
Jet packs
Idk about Star Wars. Feel free to add.