I tried both he ways firstly by using the Addon and then directly on the website.
First Attempt:-
1.selcted the model in the viewport .
2.Fill the various fields provied by the File/Io (sketchfab Addon) option likeTitle ,description,tag.
3.paste the API key, and click on the upload
4.and all i get is greyed out model in the sketchfab(no material applied that i used in blender’s cycle render).
5.I can even see my materials in sketchfab’s 3D setting menu.
6. I have not used any texture map here…except procedural texture like voronoi and wave.
7.Link to sketchfab:- https://sketchfab.com/models/f3739552a69d4dfc9fb44940c62911d4
Second Attempt:-
1.Exported to Wavefront(.obj) in the viewport.
2.went to Sketchfab Website and Uploaded the OBJ and MTL file that i generated in step 1.
3. but again the same result.
4 Link :-https://sketchfab.com/models/2c8dc168d7c749399fd2a67b20507fad
I search for this on internet and people are saying that sketchfab doesn’t support Blende’s Cycle material…if it is true..is there any other option to uplaod the model