That product exists, and it's called Quick220. The Y extension lead would work, except that if either outlet has line and neutral swapped, you have a dead shor

That product exists, and it's called Quick220. The Y extension lead would work, except that if either outlet has line and neutral swapped, you have a dead short, and if you pull one of the male ends while charging, you have a live male prong. Quick 220 mostly resolves this, but you still need a 3 lamp tester, IIRC. https://hackaday.io/project/4818-a-quick-220-clone https://hackaday.io/project/4818-a-quick-220-clone https://quick220.com/ https://quick220.com/