[Malte Müller]

I would understand “underrated” as not so known for the general public which we surely don’t count as 😉 Since here are quite well known ones listed I name a few more of those:

– Fellini/Rota
– Sautet/Sarde
– Lautner/Sarde
– Polanski/Komeda
– Truffaut/Delerue
– Leone/Morricone (only 6 if you don’t count Leone produced ones)
– Besson/Serra

Also rather well known:

– Angelopolous/Karaindou
– Lee/Blanchard
– Avildsen/Conti
– Singer/Ottman
– Kurosawa/Sato
– Gerry & Silvia Anderson/Barry Gray

A few German ones:

– Petersen/Doldinger (7 movies unless I missed one)
– Schlöndorff/Doldinger (3 only)
– Schlöndorff/Henze (3 only)
– Wim Wenders/Jürgen Knieper
– Joseph Vilsmaier/Enjott Schneider

And for fun a director itself underrated for a reason 😉
– Uwe Boll/Jessica de Rooji