"Wish granted. Electrons, being a human construct, have now always been defined slightly differently. Just as Franklin got the polarity wrong and you still use his labeling system, J.J. Thompson will now have fundamentally misunderstood the nature of the electron, leading to a cascading assumption by later scientists that the number of electrons in a neutral atom is one greater than the number of protons. Even though this completely breaks the math of quantum mechanics, everyone is just used to subtracting one at this point. This is a minutely worse world, but as a bonus, every physicist who sees you will now be preternaturally certain that you are personally to blame. You're welcome."

Former situation: there is one electron

New situation: there are two electrons

I always liked the idea that the genie rules, when they're presented, are not laws/rules so much as hard physical limits. You can't wish for more wishes because the genie just doesn't have that much power. They're powerful, but they're not God with a capital G. The genie tries to add a electron to every atom in the universe. If fails and collapses with exhaustion before it's even finished adding one extra electron to every atom in your body.

Genie is being lazy and interprets that as: Add one electron to the universe, and attach it to any of the atoms available.

Can someone ELI5 what would happen?

Ha! Tricks on you. There was only ever one electron in the universe anyway. Now they can split the work and get twice as much universe done.

no need to go to such lengths, it's enough to add one singular extra electron anywhere to brick the whole universe

You’re always so negative …

Diabolical…..

Barbaric.

Just make ionic bonds a little stickier for a minute.

What if it’s one extra neutron? >.>

I'd add a proton, tbh

Or make every living thing deeply aware of each of their atoms at all times