Hello "Miguello80",
I use these
BM-6072 and yes, the outputs of these boosters are connected in parallel, means red wire (+) connected to red wire (+) and black wire (-) to black wire (-).
The inputs of these MPPT-boost charge controllers are each connected to an own PV circuit (2 panels each, in parallel at my side but it should work in series too).
You can't connect both mppt controllers to the same PV circuit... they would drive each other grazy (even MPPT / PWM controllers interfere with each others).
Recently I discovered that you can manually adjust the max. output voltage, but it's very fiddly with the tiny buttons, the tiny LCD and the user unfriendly menu.
Finally I managed to set them to 84.5V each.
I've checked
these MPT-7210A controllers as well. But the over all power output is way poorer than with the above linked BM-6072.
Both MPPT boost chargers (MPT-7210A and BM-6072) will work without a battery at the output... and they start up when the sun is rising with the previously stored settings.
I even bought
this controller too (60A version), but it's still unused in its original packaging.
If you are interested, I'm sure we will find a deal

.
It would require that I connect all 4 PV panels in series to connect them with the controller. Because it's not a boost type controller, so the input voltage always (even in a cloudy situation) needs to be higher than the output voltage.
But I don't know if this type of controller will work without any battery at the output (it might need power, even during the night, when you would like to retrieve data via RS485).
My first attempt to charge the E-Odin battery (or the 72V/20Ah batteries of my Futura Classico LI) was with these
DC-DC boosters, but that was very problematic when a cloud moved between sun and panels -> finally it fried me the HY3912 MOSFETs at two of these circuits. These modules can't cope with an unsteady input power.
So I stick to the 2x BM-6072 solution, because it works and it is performant. But it requires 2 disjunctive input circuits.