Passport/Visa

EU members need just a valid passport or identity card

Health

Malta is an island particularly sane, without dangerous fishes or poisonous animals.
No vaccine mandatory, no specially medicaments to wear, water perfectly potable.

Electricity

240V, 50H
Plugs are Germans, with three flat shots, and sometimes rounds.
Hotels provide adapters almost always, and in any case, you can find them easily in stores, paying around 3LM