We take data from arcgis online map with coords like [8530892.965585379, 5422690.331037998] spatialReference: {wkid: 102100, latestWkid: 3857} (as on screenshot). Then use online converter to get coords for Google Earth (EPSG:3857 WGS 84 / Pseudo-Mercator -> EPSG:4326 WGS 84). And see mismatch for about 65 meters (on 2nd screenshot). Why? How to align coordinates.
As I've said before, the G in GIS isn't Google...
Is 65 meters an issue for you? I mean do you need better precision than that? If so perhaps you need to consider a different work flow for your conversions. Remember too that various projections and spatial references may and often times do use different datums. Consequently, a conversion may induce 'error'.
We are installing drip irrigation and even 5 meters is an issue. Is it possible to obtain google-compatible coordinates using the source data?