for usa i found this https://www.electricbike.com/electric-bike-law/
extract:
if you are operating as a moped in California, you DO need a moped license plate.
It can get really confusing, and very seldom does any one place you look have all the information you need. You need to get your information from official state websites or publications. Looking at the wiki for California, it contains a very obvious mistake. Lots of misinformation on sites that try to summarize the laws for you.
Don’t just trust what a person that wants to sell you an e-bike says. There is no substitute for digging up the law in your own state to figure out if what you plan to buy, or have bought is legal for you to ride in your state.
Summarizing the three states we just looked at, the example e-bike is not a “bike” in any of the three states. It’s not a bike in Texas and California because it can motor to 23-MPH. In New Mexico, there simply is no such thing as an electric bicycle.
But it’s pretty easy to limit any e-bikes speed, so the e-bike could be slowed down enough to be legal in any state with a 20-MPH limit. In New Mexico though, nothing will make it a “bike” IF the motor is turned on. With the motor off, nothing prohibited carrying a motor you are not using on a “bike”. What’s the difference? You could pedal legaly on the street, then once off the street, motor happily off road.
In two states, California and New Mexico allow riding as “moped” class. The moped class in both states allows 30-MPH. Both require a drivers license but only California required a motorcycle endorsement for the license. California required a registration, New Mexico does not.