I readed some of the chapters of the Dragon Ball Super manga, not all of them. In the ones I've seen, Trunks never turned into Super Saiyan Rage. But now in chapter 23,
Zamasu says to Goku that even Trunks could be stronger than him
Even if this is accurate or not, Trunks would have to be very strong to raise such doubt. This doesnt make sense if he only can transforms in Super Saiyan 2, because that transformation is 3 stages below Super Saiyan Blue (behind SSJ3, Super Saiyan God and Super Saiyan Blue), and in other hand Super Saiyan Rage is more or less in the level of Super Saiyan Blue, it can be in the same level, slightly weaker or stronger (personally I think it's a stronger transformation, but there is no official info on this yet) So my question is, did Trunks turned into Super Saiyan Rage in any chapter of the Dragon Ball Super manga?