That can't be done. You can only 'save' attachments from one mail via the GUI. And that doesn't mean that they are deleted. They just stay inside the mail unless you delete them.
I'd make a new personal pst file (assuming you run MS Outlook). Then copy selected mails to that new pst file, delete them from the inbox (or whereever they are now), then compact the main pst file.
Don't forget to include those personal pst file(s) in your regular backup.
Whenever I'm trying to send/ receive a new email in my Outlook, I'm getting an error 'Your Outlook mailbox is almost full, please reduce your mailbox size.' I think this is happening due to heavy attachments in my Inbox emails. I don't want to lose my email attachments so, can anybody tell me how can I export all attachments from my Outlook at once?
Many Thanks!

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