I found this article where John Nelson explains how to make a basemap monochrome. But can I save it and make it available in the basemap gallery?
https://www.esri.com/arcgis-blog/products/arcgis-online/mapping/how-to-make-a-grayscale-or-monochrom...
I would like to be able to take it out in the field in e.g. Field Maps too.
