What exactly are balanced in Apex League?

The ranked PvP system present in game (global release) named Apex League is said to be balanced with the following arguments
 Weapons are boosted to their max level and max advancements (just own one copy of a weapon and you can use it in Apex League)
 Relics are boosted to their max advancements (just own one copy of a relic and you can use it in Apex League)
 Matrices are not taken into account
 Simulacrum traits are not taken into account
 Weapon resonance are not taken into account (does this mean: Resistance / Attack / Support / Balanced?)
https://toweroffantasy.info/guides/systems/pvp#apexleague
But there are more items and mechanics that could affect the balance, so I'm asking if the equipment (armor), the suppressor level and/or elemental resonance (like Nemesis Volt resonance or Frigg Frost resonance) are taken into account?

After discussing it in the official Discord server, someone sent me a screenshot that makes sense to me
La Ligue ultime est une arène équilibrée qui permet aux Explorateurs de s'affronter à un niveau similaire de stats de base, de stats d'armes, de stats de relique et de stats d'avancements et de renforcements associées afin de garantir l'équilibre du jeu. Les effets de résonance d'arme, les attributs de simulacre et les effets de matrices sont désactivés dans la Ligue ultime. Tous les effets de soins sont réduits de 50% et les Jetboards sont interdits à la Ligue ultime
So, those things that I was asking about are being equalized in Apex League mode:
 Stats you get from your gear (gloves / boots / helmet / bracers / shoulder pads / belt / armor / trousers / I bet the visor and the core as well)
 Stats you get from your suppressor levels
The elemental resonance, however, is not ignored (Volt resonance from Nemesis / Frost resonance from Frigg / Physical resonance from Claudia at the time of writing this answer) that gives you an elemental damage bonus and an elemental resistance bonus if you have one of the elemental resonance holder + another weapon of the same element as them
The kind of resonance that is being ignored is the Attack (more damage) / Resistance (more resistance + better shatter) / Assist (more healing) / Balanced resonance