I've checked through most follower mods, and I'm pretty sure that I've never seen this feature.

Basically I'd like to be able to use certain skills of my followers instead of my own. Example: My character doesn't level lockpicking because he's a big clumsy warrior guy. But he does have a follower who is a sneaky thief with great finesse. Would be great if I could ask him to try his hand on that locked chest like how he'll help me press a button.

Since lots of followers have skills beyond just 'combat' skills, I would like to have them do things based on non-combat skills. The lockpicking one seems the one that's most useful. Give your follower a set of lockpicks and have him/her try to unlock a chest/door based on the number of lockpicks, his/her skill and difficulty of the lock.

It would give even more varied use for followers, especially those who might not have particular good combat skills, and makes you feel more like a traditional D&D party too.

Other ways feel a lot tougher to implement. I guess for example an Alchemy proficient follower could be made to 'use' an Alchemy table. Maybe only 'ask' him to make a set of basic potions for Health, Magicka and Stamina, and maybe Resistance potions; the quality would be based on his Alchemy skill. You'd still provide the ingredients. Even extend this to the other crafting abilities for Smithing and Enchanting.

This would really help you appreciate having a large and varied follower party, and also lets people who want to focus on fighting and combat to focus on those skills for their player character, while the followers actually support him outside of combat too.

But it sounds really complicated, especially for crafting. Right now I think I'd be glad to be able to have a follower pick a lock.