It's simple:
Contact lenses.
I don't get why every assumes it has to be Iron Man type lenses when we've gotten that in a standard cowl (The final scene with Joker vs. Batman in the Dark Knight) and it didn't look great, where as the Arkham Games and recently Batwoman took the contact lense approach (with the glowing eyes being representative of detective mode/night vision) and it looked great while maintaining the freedom to switch to the traditional normal eye look that adaptations use.
There's no way to make the drop down, Iron Man style lenses look good/natural unless he's in an armored TDKR suit like he was in BvS. With Iron Man style lenses you lose the expressiveness of the natural exposed eye. That's not the case with contacts. Contacts are the way to go.