on 11-04-2020 01:32 PM
Easy answer, no.
Email app settings on one device will not change the settings on another device.
But there is a caution. If your email app is set up as a POP3 account to communicate with the TalkTalk mailbox and that POP3 account has a default setting of downloading and deleting mail messages from the server then those mail messages will exist only on the device you download to. So they'll not be seen in the Inbox of the other device.
If you're using multiple devices it's best to set up all email accounts as IMAP accounts. That way they all see what's in the Inbox and other folders on the TalkTalk Mail server.