@Sparkadoodles 

Hi, please plug them into wall socket directly, because some power strip might have filter function which will block the powerline communication.

if two powerline adapters are plugged into the same power strip, it should be okay, but usually we need to use them at different locations of the house, thus it might be not possible.

By the way, TL-PA7017P has an additional power passthrough on the front, so you could also connect other electrical appliance to its passthrough.