How about letting the Essence Remote stay in BT mode - using both should not cause any problem as far as I know.

MM

What is it you want to control? Does it need IR or can it be bluetooth also?

I use an Essence in IR mode to adjust the volume of my Beolab 50s. The eye is located on the floor behind one of the 50s.

It needs to be in IR mode, since I'm living outside the B&O ecosystem. I've implemented an openhab server which receives the IR codes from a connected eye and controls all devices. (TV, Marantz AVR, kodi media center, itunes library, lights and soon the new fireplace)

I would use it mainly to power up music sources and volume control while working or sitting in the dining area.

(Ideally, bluetooth would be better, also for the BeoRemote One, it's quicker than IR signals which need 200 msec for each command. I can connect my BR1BT to my computer (a mac running the openhab server), but I couldn't find a way to receive and interpret the BT commands. It does change volume and track on the itunes, but that's it.) > So it needs to be in IR mode.

The Essence remote has mighty IR power. There are multiple emitters and they're very strong! You can have it mounted on a wall and have an IR receiver mounted on the same wall at the other end of the wall and the IR signal will still be received.Just think about that for a minute: the IR signal is being sent along the same plane as the IR receiver to the SIDE of the IR receiver rather that straight-on.

Yeah, but in a straight line along a wall is pretty easy for IR, even if the receiver is pointed in the 'wrong' direction. 

In my case, many things are blocking the path between transmitter and receiver. The signal needs to bounce off several walls/ceiling to reach its destination.