Using Go 12, when you print the print dialog has an option for PDF and that leads to one for email.
When you print or save to pdf the entire layout is used which should include pictures, etc.
With the new free version of Go 12 you could have your clients download that and you could send them a Filemaker file but don't forget to create accounts and passwords. Maybe compress it with a password for security.
FM reworked its container fields for media in version 12 and added some great new features especially for client-server (e.g. FM Go with 3G to FM Pro or FM Server). So it's premature for anyone to say what best practice is now. This video on youtube gives a good overview with demo:
(FWIW, I'm leaning towards external/open storage with interactive streaming for my stuff.)