I bought a refurb 3, it turned out to be a Japanese unit with some Japan specific nfc hardware and software.Since 6 was not launched in India, it is basically a US refurbished unit. I purchased a Pixel 3 that way. eSIM is disabled, physical SIM is unlocked for all carriers and the bootloader is permanently locked. Although it may vary, I think most of the cheap refurb units are basically the carrier unlocked ones, rather than the ones sold unlocked.
Osaifu-Keitai - Wikipedia
en.m.wikipedia.org
I also had a 4a that i had bought unlocked from USA retail (best buy) and it supported esim.