Do we need a thread about the 2019 EU parliamentary elections? Not sure where on the forum to put one. Talk of/about UK participation in the election has recently gained momentum, given that the option of pausing Article 50 is widely considered now to be a real possibility.
We'd need to rush a bill through Parliament to repeal the repeal of the EU Elections. The repeal was quite complicated as the election law had entwined into dozens of Acts (see the Boundary Reviews thread), but the repeal of the repeal might be fairly simple.
You could do it in one line by revoking the Repeal Order. The Repeal Order doesn't come into force until we leave.