There are many settings in Dynamics 365 Online that can be changed via the PowerShell, such as this one, https://docs.microsoft.com/en-us/power-platform/admin/enable-rich-text-experience, for enabling rich text in the description field of appointments.
There is an alternative to using the PowerShell which is to use Organization Settings Editor managed solution released by Sean McNellis of Microsoft.
Download the solution from https://github.com/seanmcne/OrgDbOrgSettings