After you have enabled anonymous links for SharePoint Online tenant, you can set what access level the links can give: edit or only view. The setting is global for the entire tenant. You can choose between
Edit - anonymous links will allow to edit documents
View - anonymous links will allow only to view documents
None - users can decide about the access level on per-document basis (no global setting)
The script is related to and more described in a Wiki article SharePoint Online Sharing settings with CSOM.
It requires SharePoint Online SDK.
#Paths to SDK Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.dll" Add-Type -Path "C:\Program Files\SharePoint Online Management Shell\Microsoft.Online.SharePoint.PowerShell\Microsoft.Online.SharePoint.Client.Tenant.dll"
#Enter the data $AdminPassword=Read-Host -Prompt "Enter password" -AsSecureString $username="admin@TENANT.onmicrosoft.com" $Url="https://TENANT-admin.sharepoint.com" $LinkType="View" #Edit, View or None
#Enter the data $AdminPassword=Read-Host -Prompt "Enter password" -AsSecureString $username="admin@TENANT.onmicrosoft.com" $Url="https://TENANT-admin.sharepoint.com" $LinkType="View" #Edit, View or None