Macbook Pro keeps waking from sleep during the night and draining battery
Broadly speaking, what I would do next is as follows:

1. Quit all applications and put the MBP to sleep overnight. Then, 


If it's still draining battery power significantly, it's time to reset the System Management Controller (see below)
If it didn't drain the battery much during the night, then proceed the following night with only two or three apps running. 


If it significantly drains the battery, then you've narrowed it down to one of those apps, so repeat the process until you identify the culprit.
If it doesn't drain battery, then repeat the process the following night with a different group of apps and repeat the process until you narrow down the app(s) causing the problem.



2. Reset the SMC


Fully shut down your MBP. 
Press and hold the power button for at least 10 seconds
Let go of the power button and wait 5 seconds
Power up your MBP again


Once you've reset the SMC test your MBP again. If it's still misbehaving, reset the SMC again but with the following steps instead:


Fully shut down your MBP. 
Press and hold the right shift key and the left option and control keys for 7 seconds before then also pressing and holding the power button (or Touch ID button) down for another 7 seconds (i.e. the keys will end up being held down for 14 seconds, the power button for 7 seconds)
Let go of all three keys and the power button
Wait 5 seconds
Power up your MBP again


Now test your MBP again. If you're still having problemss, let us know.