I don’t think Traveler’s Checks work anymore. When I travel I take a debit card and withdraw money there. Just do your research and stay away from the high-fee machines. Especially in Europe, if it’s blue and yellow, stay far far away.
Their Travelers Cheques page shows a picture of me reading a paper map 40 years ago. As long as you are using a century-old money technology, why not use centuries-old map tech, too?
American Express still offers them. I used to use them when I was in the service and traveling halfway around the world . Never had a problem using them. That being said, I have not used them In 40 years.