Power recirculation rig using rectifiers and BLDC motors
1st note: The BL_Heli ESC won't last for long, since it is meant for RC planes, cars, etc.. they don't work at nominal power all the time, aka S1 duty.

2nd note: with this circuit you won't be able to control the torque. Only when generator voltage will become higher than battery voltage, the generator will produce a negative torque.

As said, this would reach the equilibrium when generator would produce higher voltage than supply voltage, and in a very short window it will freely run and in a very small rpm increase it will prevent further speed increase. Of course the two motors may not have the same characteristics to achieve this.