Well you would need a passport obviously
Discussion
I have a cyber-security privacy guru who suggested we try that (not removing hat and sunglasses)m& not giving passport to hotels/AirBnBs when we stayed with them) &when we just this past summer traveled to Europe. They wouldn’t let us pass the gate without removing hat an sunglasses. Electronic scanner was not keen on accepting my passport twice, but was fine with nostr:nprofile1qqswvecv67selg4kt6798430saw09y2mx7g93gdhm8cqzdzw8t6fr0cpz3mhxue69uhhyetvv9ujuerpd46hxtnfduq36amnwvaz7tmwdaehgu3dwp6kytnhv4kxcmmjv3jhytnwv46q5yfxss ‘s. Every single host asked for our passports to copy. It was very uncool. nostr:npub18dlusgmprudw46nracaldxe9hz4pdmrws8g6lsusy6qglcv5x48s0lh8x3
I don't think it would work flying internationally. Basically have to have a passport no matter what. But was surprised to see it work for domestic travel.
Afaik you can tell them they can't copy your passport under EU's data protection laws. They can ask to see it and write down the name and number, but you can tell them to fuck off if they want to copy it.