Light Burn?

It doesn’t seem like light burn, as there aren’t any crispy, burnt edges on the leaves. The curling which seems minimal to non existent could be from overwatering, low humidity, or maybe too much nitrogen in your feed, even though with the second plant N doesn't seem to be the issue. Try adjusting your watering schedule and light height, and make sure the humidity is in check. It might just be a phase, but keep an eye on it. You’re doing looking though, just a few tweaks! That's all I can tell with the information you gave, 🤞♥️🍀