I don't really get what you mean. L3 and R3 are buttons, not triggers. Only L2 and R2 can eventually be triggers, depending on the pads. Easy to notice : when you map triggers in ES, they are marked as Axis, not buttons. The analog joysticks are handled, no problem with that.
I'm sure i didn't answer your question 😮 but recalbox handles everything itself : hats, buttons and triggers/axis, and sets the emulatir up accordingly.