Also, it's kind of funny how you say it has absolutely nothing to do with Brexit and immediately jump into an anti-EU rant, probably not the smoothest transition :D
Honestly, the EU27 have their own home-grown grid problems to deal with[0], helping third countries transit power through the EU territories must be right at the bottom of the list!
Austria and Germany had a single electricity price zone ... until October 2018, one of the reasons blamed for the split was "slow grid expansion"[1].
[0] https://www.euractiv.com/section/electricity/news/german-ele...
[1] https://www.apg.at/api/sitecore/projectmedia/download?id=24f...
Obviously- that may be wrong, but let’s see, would be cool if it’s true.
These things are all matters of fact. From the EU's perspective these things are not "negative" exactly, but merely the way they play the game. Everything is connected to everything else and any inter-dependency may become leverage in any unrelated area of cooperation at any time.
My understanding is that:
Acting as a group the EU has made some "pragmatic" decisions like fishing in western Sahara waters, but probably found it relatively easy to turn down less economic and/or more illegal activities as a block. If the UK were to more fully ignore UN decisions and accept natural resource from the disputed lands, the loss of respecting the rules is much more a loss for the EU than Morocco.