Mussolini went to the east front only in august 1941.
He flew with Hitler in a Condor to Brest-Litovsk on 26 august and from Krosno to Uman on 28 august, "piloting" the aircraft for a while on the return flight, even though I don't know where they landed.
https://www.youtube.com/watch?v=wsTdq-ThN9k at min. 1,06
Gianandrea