I have 207 geodatabases, each with 3 feature classes, and multiple shapefiles (point, line, and polygon) within each feature class. The data is from The National Map (USGS). In the screenshot, you can see three of the geodatabases - Cornwall, Danby, and Dover Plains - with their feature classes. My goal is to merge (or append) these 207 geodatabases into one geodatabase that maintains the same feature classes (most important: foundation, gaz vector, and hydrography). I am not well-versed in Model Builder or Arcpy. A cumbersome method would be to append each feature class individually within each geodatabase with the master geodatabase as the target.
How can I make this process more efficient?