Don’t. Even if you understand what you’re doing, someone else won’t and your family will die in a house fire.
Male-to-male end cables allow for the two leads of an open male end to make contact with anything conductive (including your flesh, causing some pretty gnarly burns) to complete the circuit and start a fire. No conscionable electrician will make these for you. It is the dumbest solution to any problem you’re looking to solve. Don’t.
Just a reminder coming up on Christmas.


I have yet to encounter a European counterpart that compares. (Italian electrics in particular are downright dangerous).
UK plugs are the best in the world. Fight me.
https://youtu.be/UEfP1OKKz_Q