Does the iPhone X have eSIM? No

No, the iPhone X has no eSIM, so it cannot take a travel eSIM. You need a phone that supports eSIM, or a physical SIM card at your destination.

Check your own iPhone X

Two minutes on the phone itself settles it, whichever version you have.

Dial *#06#
Open the phone app and dial *#06#. If a number labelled EID appears, your phone supports eSIM.
On an iPhone
Go to Settings, then Cellular (or Mobile Data). If you see Add eSIM or Add Cellular Plan, it supports eSIM.
Check it is unlocked
A phone bought from a carrier on contract may be locked to it. Ask your carrier, or look for a Carrier Lock line in your settings that says No SIM restrictions.

Share a companion's travel eSIM, buy a local SIM or roam: which one fits your trip.

Every Apple model we have checked, with the versions that leave eSIM out.

The 30-second check for any phone: the EID, and whether it is unlocked.