Generally speaking, batteries in hand luggage must be less than 100Wh, which is the case with this battery. For information, mine has already been on a plane once and didn't cause any problems at the checkpoint.

Most airlines allow up to 100Wh capacity. This was purposely designed to be just below travels no problem

Yes, I fly regularly and always have the Prime in my hand luggage, even in the USA it was never a problem.

As others have written, most airlines allow power banks up to 100Wh. This one has 99.54 (also labelled as such below). I am currently travelling with it and have never had any problems. They didn't even want to take a closer look at the powerbank.

No, that shouldn't be a problem. Just back from the USA. Just put it in your hand luggage, not in your checked luggage.