How to Remove Old Email Accounts
From your screenshots, it looks like old logins saved in Chrome. If you've used Chrome to remember your login details for websites, that's what they'll be. They're synced across desktop as well as mobile Chrome installs via your Google account. The UI for selecting which login to use has changed recently, so it's natural that you might be surprised by it.

You can delete old login details from the Chrome settings, on PC or mobile. On Android, the steps are:


In Chrome, click the three dots button in the top-right
Choose Settings from the menu
Choose Passwords
Either turn off Save passwords to disable the feature entirely, or:


Click a site in the list
Click the bin/trashcan icon in the top-right to delete that password
Repeat that for all the old login details you want removed