Nope it has a tail sting cooldown attack baseline, it just does not matter in the scope of actual scorpion build choices, as no passives effect it.
https://www.lastepochtools.com/minions/primal_scorpion
it applies two stacks of poison with longer durations,
This is just a long standing problem with the “poison” tag.
Things dont get it unless they have either DoT poison damage(As per mike many moons ago, hit damage is never poison type. So even a skill like serpent strike which gets the tag, adaptive damage is all physical.)
And adding ailments to a skill does not grant it the correct tag. Getting bleed chance on a skill does not trigger it to become a physical skill. Spirit plague can never get physical or poison tags despite its ability to apply plague, summon poison wisps, and bleed/poison.
So because poison the ailment rarely gives the tag(I honestly couldnt tell you why serpent strike gets it.) and no hit based skills get it, and heck the said poison wisps from spirit plague minion tags are necrotic/minion. And the spell it uses has a poison tag, but minion skills dont get skill levels so its a moot point.
I guess the main question would be, is there even a poison specific minion option for +levels to poison minions? the scorpion still does poison damage baseline with its tail sting, and will still scale with minion poison damage regardless of tags.
edit: honestly most minions dont count as their respective damage type skills. Skeletons do physical baseline and have the minion tag of physical, but wont be buffed by things that grant +x physical skills. As their skill tag is just int/minion. Thorn totem is able to gain the poison tag thanks to its rotten core ability, but that just adds poison minion tag, so +2 to poison minion skills would buff it, but +2 poison skills would not. A example is logi’s hunger amulet. it grants +2 to fire minion skills. And works on pyromancers, but pyromancers are not buffed by using cinder song which has +1 to fire spell skills(pyromancers have both these as minion tags, but because we are missing the minion keyword it does not apply)
Currently there seems to be no way to even gain benefit from poison minion tag, so its kinda a whatever point, but could be fixed for clarities sake.