Unfortunately it doesn't seem like that is possible at the moment. But that would be a great feature request to the Gmail team.
In the mean time you could try a work around. You can use a Google Sheet that connects to your Gmail to allow you to view/filter and sort by email size. The sheet is called Gmail Sort by ctrlq.org
How To:- Copy google sheet to your Google Drive from this link
- From top menu select
Gmail Sort > Scan Mailbox - The script will require authorization to scan your Gmail inbox. It is an open source script created by ctrlq.org (check it out here)
Check out this post for more info: Sort Gmail Messages by Size