Dual Motor ESC Wiring

I have two RC ESC that I want to use for driving two motors from one controller.

I have two choices, the 1st one Y controller adapter and one Y Parallel battery adapter 6S2P


Second option, one Y controller adapter and 2 batteries (no parallels) 6S1P


Which is the more efficient?

The 1st option is more simple, to charge for example. They are both same efficient. Some rc flyers use the 2nd option cause if something fails they can land their plane with 1 motor.