Search for the object SKILLS_DATA_MANAGER in the esoui sources.
It's created here from class ZO_SkillsDataManager
https://github.com/esoui/esoui/blob/...nager.lua#L274
And provides functions to get the skills info like
GetCraftingSkillLineData(craftingSkillType)
https://github.com/esoui/esoui/blob/...nager.lua#L245
The skillLine should have an index then which can be used with other functions to get the name, rank, morph etc.
e.g.
IsSkillAbilityPurchased(skillType, skillLineIndex, skillIndex)
IsSkillAbilityPassive(skillType, skillLineIndex, skillIndex)
Hope this helps.