I'm going to put a plug in for my new PAYG eSIM called Bcengi. Instead of the typical eSIMs, where you buy fixed data bundles for specific areas that expire, Bcengi is a pay-as-you-go eSIM. You load a cash balance into your account and pay only for the exact amount of data you use. The network adjusts rates and connects automatically as you cross borders into different countries. When you get home, you can turn it off, and then turn it back on again the next time you travel outside the country.
So there's no need to buy separate eSIMs for different countries or areas, and you don't lose any leftover data at the end of it. It worked really well for me. I used it in Norway after my T-Mobile slowed down for about ten days and spent $6.88. I used a credit card to pay the deposit (minimum of $10), which automatically reloads when your deposit starts to run out. And you can stop the automatic reload at any time. https://www.bcengi.com/
The best thing is that you don't waste any data. For example, if you buy an e-SIM that costs $$ for 5 GB of data and you only use 3 GB, you lose that third GB when you leave the country. With Bcengi, it just stays on your phone until your next trip or whenever you want to use it. And in fact, I used it at home last week when we had a thunderstorm that took our power out for a couple of hours. I have T-Mobile, and whenever there are bad weather issues, it just goes kaput, so I had no cell phone service. I switched my e-SIM from T-Mobile to Bcengi and used it for the two+ hours that we didn't have power, and it worked great.