Min IAS couple on the EC175 is 30kts, but it will engage GA in the hover. If no AP presets already made it will automatically select Vy and 1000ft/min RoC, otherwise it will use the presets. One of the reasons we don’t routinely use it from the hover is that if you are OEI below Vtoss (which in a 175 on the N Sea is always 40kts) it will prioritise getting to that Vtoss, which may result in a a rate of descent. However, it gets to Vtoss pretty quick so under the vast majority of N Sea conditions you would be unlikely to see much RoD if any. SOP is to engage GA at Vtoss.
Helpfully, if there is no lateral mode already coupled, then it will also roll wings level as well as accelerate and climb. It does that well enough and quickly enough to use as a Get Out Of Jail Free card in disorientation scenarios similar to that being discussed.