I have been attempting to run powershell as my terminal on windows in pycharm, so I did the following:
As of this writing (2018-9-20), there is now a PowerShell plugin available here.
I have installed v1.1 in PyCharm v2018.2.3 (Professional), and it seems to work like a charm, no pun intended.
This plugin provides Intellisense-type support of PS1 scripts, as well as an integrated PowerShell terminal. In order to open the terminal, go to Tools > PowerShell Console...
There appears to be no need to muck about with any kinds of settings or permissions in order to get it to work. It Just Works.