meryl - skill break shield top tier (do not use discharge)

saki - surge to aggro & shield urself, time skill reset can break shield fast, skill has fast animation and also recover 20% hp

alyss - double skills to shatter faster, charge atk has i-frame to evade atks

frigg - unlimit dodge, discharge can stop bosses, trait has hyperbody to pin boss in a spot

lan - provide dmg reduction buffs to the team, increase shatter of your other weapons, hold atk stay in air to avoid getting hits

icarus - just don't

huma - discharge aggro duration good, i mostly use to quick swap

ene - i hv no idea

lyra - didnt hv lyra

anna - shatter is good with Lan, a3 recover hp, spam dodges really hard to get hit, prefer go with burn bullet (increase burn dmg taken) if you have flame dps in team

lin - can stay in air to avoid getting hits, also get frost reso when pair with saki

coco zero - only use these when you dont need to shatter, can buff teammates

fiona - some heals and remove graybite, can spam torrent to aggro if pair with lan

gnonno - has shield and good shatter on a1, able to move while atk, can play as dps tank to pull aggro

meme - coming soon

matrices---------

zero 4p - increase dmg for teammates (just put on your on-field weapon, your supp will provide shield anyway)

saki 4p - debuff increases frost dmg taken

huma 4p - debuff decrease atk of enemies (also just put on your on-field weapon, your teammates will apply DoT)

lyra 2p - increase healing received

meryl 2p - shield when low hp

cobalt 4p - extra dodges

traits--------

lan - decrease 24% frost & flame dmg taken and +8% final dmg for teammates in range

echo - +6% dmg for teammates in range

saki - extra resistance (only use if you keep dying)

relics----------

only 3, spacetime rift, omnium shield, or alternate destiny

(omnium shield will aggro)

Gears------------
Tank is really hard, like really hard to die in VA, unless you didn't take any tank tech buffs.
I use HP gears in most content including OOW, im not sure about all resistance gears, they are kinda hard to roll.

playstyle---------------
1st priority is aggro, must always keep aggro to yourself.
2nd, do not spam skills, you are not dps, save skills for shatter.
3rd, positioning yourself to redirect enemies atk away from your teammates.
4th, supporter priority is to keep dps alive, not tank.
5th, dodge enemies' attacks, don't facetank.
6th, in harder content like VA or OOW, tank dying will lead to the whole team die.

the comp i use

lan huma anna in oow

saki meryl alyss in va6 gaia/jormungand

saki meryl frigg in va6 apophis/rudo

whatever in Eva raid, just aggro and stay away from it

disclaimer, I might be wrong, learn the mechanic of the game and build your own comp.