Well… it depends. This can be easy if you know the steps for preventing a shock from 220 volts, preventing the tank from collapse as you drain it, etc.
It can also be one of those weekend nightmares without hot water. The element seat or threads can be corroded in the tank so a new element won’t go in without a leak. The tank could be on its last legs. When was the relief valve checked?… they do fail when checked sometimes. There are so many ifs.
I prefer having an experienced plumber arrive with fast access to the right parts and a new water heater in the wings.