I tried to reproduce your problem - in vain. Copying and pasting email address in a column of the same type - plain and simple - works.
Importing email addresses by importing a CSV file also works flawless as shown in the 2nd half of the screen capture.
It’s unclear what you mean. What connected rows are you talking about? Email columns do not have connected rows. More generally, CSV files contain individual tables without any links.
Do it like thousands of other people who have used SeaTable to develop powerful processes and get their ideas and tasks done more efficiently.