Is there a way to upload a saved symbology file (.qml) from QGIS and upload this into AGOL? I cant see any options?!

[George_Thompson]

I did not see .qml on the supported list: https://doc.arcgis.com/en/arcgis-online/reference/supported-items.htm

Is there another format that could be exported that may be supported?

[LottieLeigh-Browne]

I can also export the symbology from QGIS in .sld. Doesnt look like this is supported either?

[jcarlson]

You can put it into a .zip archive and upload that, although you'll need to tell AGOL that the ZIP is a shapefile or GDB.

You may be better off opening the layer in an ArcGIS Desktop program and exporting a style file from there. If you just need to host the QML for others to access, consider using a more generalized file platform like dropbox, or even GitHub. AGOL is really meant for use with ESRI products.

[RussRoberts]

Currently this is not supported. Are you using points lines or polygons symbols?