In Solus AFAIK there is no way to share folders over the network using graphical tools, I also believe this functionality should be provided in the default image. Using nautilus-share we can share folders using the samba usershare by simply right clicking the folder in nautilus and selecting sharing options.
Some manual configuration of samba is required to enable usershares to allow nautilus-share to work
In /etc/samba/smb.conf you'll need
[global] ... usershare path = /var/lib/samba/usershare usershare max shares = 100 usershare allow guests = yes usershare owner only = no
Use testparm to test your smb.conf file for errors
Restart the smb service with systemctl restart smb
Use net usershare info to determine if usershares are enabled
You may need to manually create /var/lib/samba/usershare and set appropriate permissions on it (see ArchWiki samba usershares section)
I tested by sharing my Video folder and nautilus on my laptop as well as my Android device could see the share and play videos no problem. I still need to test accessing the share from Windows but I assume its working.
There is probably a more elegant way of enabling usershares that I haven't figured out, if you don't think this functionality should be provided by default,
at the very least could samba be configured to enable usershares by default, so nautilus-share would work after installation without any configuring.