Vin pin vs USB vs Barrel connector: Wemos D1 R2
The D1 R2 uses the same power supply arrangement as the Arduino Uno (albeit with a better switching regulator for the 5V instead of the Arduino's basic linear regulator).

So it should be safe to use both the USB and the barrel jack at the same time.

The NodeMCU doesn't include a 5V regulator and doesn't have the power switching circuitry of the Uno / D1 R2, and thus is a completely different arrangement.