Asklemmy

IEC 60906-1 (Type N). It was designed to be an international standard. It has no reverse polarity and is small but secure. It comes with all the important safety features and is also compatible with Europlugs.

However, the EU has sadly recommended against switching to this plug, citing plastic waste concerns from all our current plugs. However, Type N plugs have less than half the plastic of a Schuko plug. Someone should do the math and see if it would be worth it plastic waste wise to transition to Type N. Perhaps within 10 years, the savings that come with a smaller plug outweigh the plastic waste of older plugs.

I may be skewed by the fact its the plug of my country; but i like the type L plug (its the no 1 in the photo) mostly because its modular: you dont need to get a specific faceplate to have a certain arrangement of plugs, switches etc... You just take the brace plate off and you can rearrange the fruits in the box to your hearts content. Eg: you pass an ethernet cable and need to put a keystone in the wall; you just buy the fruit and put it in the place of a blanking plate. What i dont like is the almost total lack of shielding for the live and neutral.

L5-20 and L6-30

The smallest is the best. I don't know which one is the smallest, but I want that one.

Honestly USB-C. It is getting added to electrical outlets. Super small, basically impossible to get electrocuted being low voltage DC.

Works in every country.