It doesn't seem that the Eclipse has an idle-up feature.
Does anyone know anything about this?

It does have one.
I have programed several for a few beginners. Just read the manual it's somewhere in there. It took us a while to find it.

Augusto.

I've read the manual several times and can't find it.

Unless, you use one of the flight modes and set the throttle curve to the same value for all 5 points. I guess this could be one way of peforming idle-up

By the way they're called ST1, ST2 in the manual for stunt one etc.
Controlled by the Flt. Mode switch.

Augusto.