For the Vishaps, they seem to have :
1 AoE of 1 square around them, dealing elemental damage
1 ranged attack that drains elemental energy
1 normal attack
1 long dash that deals no damages (but elemental animation)
As a minion, I would personnaly be inclined to use the elemental drain for something, as it is their most unique feature.
Since they would be minion to stronger units, I could very well see them with an elemental attack (potentially making 0 damage and just applying the element) that could drain the target's burst (which is a good upside given that a lort of VERY annoying units rely on spamming it) and fill the leader's burst (which, for stronger units is the key feature of the unit).
That way, they would be enablers : set up relemental reaction and speed up the burst (which is something to units can do so far).
A little bit like a battery character in Genshin.