Archiving a whole IMAP Folder to a file - is this possible?

I have just installed Mailspring (on Windows 11) having been a Microsoft Mail/Outlook user for some decades. I have just one e-mail account (a provider in Guernsey Channel Islands - not Gmail, Outlook or whoever) using IMAP at the server. Overall the experience is great, Mailspring is simple, logical and straightforward.

Is it possible to Archive a whole Folder to an external file?

EXAMPLE
Say I have Folder called “2022 Holiday Asia” containing 50 message. Can I archive them all off to a single file and if so what format would this be?

CONTEXT
In my Outlook previous world I would have archived the whole folder to a single file called “2022 Holiday Asia.Pst”. I would then have moved the file to Cloud Storage (i.e. off the IMAP server) and in the event that I needed to review anything opened it in a viewer (historically Outlook however online PST viewers work OK). I should add that I am not precious about it being PST format, although that would be ideal.

Regards
Glyn