WMTS services will require further research. Currently it is not clear if these type of services that are non-esri allow export tiles via a rest service similar to esri type map services. As this is will require a bit of research in order to see if implementation is possible, this will be moved to the backlog. The pdf spec is attached to this comment.
07-057r7_Web_Map_Tile_Service_Standard.pdf
WMTS services do not have a batch export option, so it would requires scraping tiles and then consolidating them into a .tpk file (if that spec was public). I would recommend that we close this issue for now.
WMTS services will require further research. Currently it is not clear if these type of services that are non-esri allow export tiles via a rest service similar to esri type map services. As this is will require a bit of research in order to see if implementation is possible, this will be moved to the backlog. The pdf spec is attached to this comment. 07-057r7_Web_Map_Tile_Service_Standard.pdf