Does this game have specific roles for characters? E.g. / DPS, Sub-DPS, Specialist, Sustain

[Nikshi]

Title

[Minh]

No. Unofficial roles are damage dealers & tanks. What's more vital is 7 main Status Effects for different purposes. Most of them are meant to deal damage.

[Nut]

IDK what you mean by specialist, but just about every character are damage dealers or contribute to damage (debuffs, buffs, status effects) in one way or another.

There are definitely units good at sustain and can aggro, but they can't exactly play the archetypical tank due to how the combat in this game functions.

A weird comparison would be like how you can "tank" in Monster Hunter, but the monster's gonna be swapping targets and no matter what you do. The same kinda goes for other roles, some characters can definitely support others, even heal, like how you can play "healer" in Monster Hunter as well, but no matter what you'll all still be DPSing in the end.

[H11DN-D4NG3R]

Techinally speaking, they attempted such a thing (with -/+ stuff, with why season 1 ids got Odd power strenght and defense) and some ids(Well, G corp Outis) made for support.
So techinally speaking, the awnser is Yes.

[SmallGespenst]

there's no real roles, some IDs are glass cannons, some are tanky and some can provide support, but most IDs will be doing all three all of the time.
Trying to categorise like that tends to erase a lot of nuance and provide an inaccurate assessment, since fundamentally; every member of the team will be dealing damage and taking hits.

[Ashen Mist]

There is some IDs that emphasize on tanking damage but in the end sometimes you can't redirect attack or not every so it is just about winning clashes, if you win clashes (unless it is unbreakable coins or enemy uses counter) you do not take damage.

[H11DN-D4NG3R]

I think Only Zwei Ishmael is the only character that can do a Tank job quite good(Her Defense Ability buff allows her to redirect All (non fixed) Attacks to herself while the buff is active)

Ofc, It isnt how you suppost to be playing anyways. given sometimes its better to have a "glass cannon" tank due to Sin+Damage type, being ineffective.