I personally really liked how Berwick Saga did it. Generics had skills there but there were also just a lot of named generics or mini bosses. And hints towards it in dialogue at some points. Berwick Saga’s skills did also generally feel a bit different than other FE games though. nearly no procc skills but much more activatable skills. You could for example find archers situated on a hill (plains with cliff tiles surrounding them) which can have Deadeye for example, and have a poison arrow. Deadeye is an activatable 3 range attack which needs you to not move, and costs you accuracy (which is actually kinda hard to come by in Berwick).
Thus if you missed the fact that guy has a skill, you will take damage for it. But it is not an automatic death, mostly just some side damage, with you needing to spend time to heal the poison (if the arrow even hits). Missing to see a skill on 1 generic was almost never an instant death sentence.
For comparison, i recall playing Fe10 randomizer with random enemy skills and that being an absolute chore. Too many skills on too many enemies. Maps which were too reliant to having certain units alive (especially early on), and skills which were practically just % chance for you to die, which feels cheap.
What is also very important in my opinion is slowly adding in skills as time goes on. If everyone starts with 5 skills, and generics have skills, and bosses have 5 skills, then that just makes everything take so long to check, that you’d rather not check any skills and get punished for it, or check them all and get bored. So you wanna let the skills trickle in over time. Another thing that could REALLY help is a proper UI. I don’t know what engine you are using (FEbuilder, LT or some other one), but if possible i would take a look at properly conveying the fact enemies have skills to the player.
You could for example have an exclamation point appear next to an enemy with a dangerous skill. Or maybe give him a slight Aura of sorts. If you’re working with a modular Character Sprite/Model system you could also opt for each skill giving you an easily recognizable design trait. Maybe every enemy with a red Headband has Wrath, and thus you can immediately see their skills based on that. You essentially just want the player to know as quickly as possible whether an enemy is worth worrying about, and how to deal with him, without going through 5 button clicks. Reduce the amount of effort to see the skills to an absolute minimum.
Also please to dear god no FEHeroes type skills with a war peace treaty between 20 nations worth of text on how to activate the skill or how it works to an absolute detail and every single situation. If you really wanna be thorough on how skills will act on (most often relatively rare) occasions, then give the skill an easy to understand description you can understand easily, and add a codex type of thing, or maybe an additional button press to extend the description to be more descriptive.
So to conclude: Explain how skills work shortly and easily. Make enemy skills be visible at a glance. And maybe even opt for activatable skills in favor of “% chance to do effect”.