Moved this to General Discussions as the best spot.
McAMTaskAgent is genuine.
There is nothing that would wake a computer by default. However, if this is Windows 10 and Hybrid Sleep aka Fast Boot is enabled, then your machine never actually shuts down, it just sleeps, so it's possible any scheduled task might waken it.
Have you checked Windows Task Scheduler, at left under Task Scheduler Library > McAfee to see if there are tasks set there? If so they could be disabled if you prefer.
The only things I can think of that would be automatically on by default are: Updates (under McAfee Updates) which should remain on, antivirus scan (under Virus and Spyware Detection) and Vulnerability Scanner (under PC and Home Network Tools).
Check there also to adjust those settings to whatever you prefer.
If this doesn't uncover whatever this is I recommend Technical Support, it's free by phone and if at first they can't solve a problem, you can ask them to escalate it to a higher level.
Just checked all those settings and they are all ok. I will contact technical support and see how it goes.
Thanks for your reply.
OK, sorry it didn't help. Good luck ;-)