Openings that reach endgames? I'm looking for some openings for white and black that have a high probability of trading queens early on without being significantly worse. Does anyone know any openings that fit this criteria?
There's a "drawing line" in the Petrov Defense for White:

[FEN ""]
1. e4 e5 2. Nf3 Nf6 3. Nxe5 d6 4. Nf3 Nxe4 5. Qe2 Qe7 {Black has to play this or 6. d3 wins a piece} 6. d3 Nf6 7. Qxe7+


Playing 7. Qxe7+ loses White's opening half-tempo, but queens are off, and if that's what White wants he's gotten it. Not playing Qxe7+ can still lead to a queen trade, until either side decides to block the e-file with minors.

The Berlin Defense is another well-known opening with early queen trade:

[FEN ""]
1. e4 e5 2. Nf3 Nc6 3. Bb5 Nf6 4. O-O Nxe4 5.d4 Nd6 6.Bxc6 dxc6 7.dxe5 Nf5 8.Qxd8+ Kxd8


This opening has gained a reputation for drawishness at GM level.