You can email a folder in Gmail by first zipping it on your computer and then attaching the ZIP file to the email.

It's easy to attach a file in an iPhone email using the new format bar in Mail with iOS 13, or in the Gmail app. Here's how ...

If you don’t already have a ZIP file created, you can simply select all your files, right-click on them, and select Compress to > Zip file. However, if you want to add more files to an existing zip ...