While not technically eInk, Pebble has an app for this, it's one of the reasons I keep using my Pebble (with rebble.io) and have a stack of backups. One thing

While not technically eInk, Pebble has an app for this, it's one of the reasons I keep using my Pebble (with rebble.io) and have a stack of backups. One thing to keep in mind, unlike a recent Apple (or Android?) watch, they do not lock after removal from your wrist, so your secrets are all button press away while you're in the shower/sauna/swimming. I store mine named using a simple/stupid braincipher instead of straight up naming them "BANK 2FA CODE".