Provision custom content type to Old & New Document Library

Hello,

I have requirement to add one custom site column 'IsGDPR' to each existing and new document library.

I am planning to create to new content type with inheriting from OOB 'Document' content type.

I will attach newly created content type to existing document library through PowerShell /CSOM

But is it there way to auto provision when new document library get created?

Please suggest better approach?