Yup. I was recently doing some night sky shooting with my E-M1.3. Not only does it do what you say, but when using its "super exposure" it'll take multiple shots moving its sensor (using its in-body stabilization) by sub-pixel amounts. This produces from a 15Mp sensor, a 50Mp or 80Mp result - and as a side-effect, the stack of images results in weighted averaging of the pixels, thus doing a fantastic job of noise suppression. And yes, it auto-aligns, at least in the 50Mp mode.
All the references I found just referred the auto-bracketing (I.e. shooting the the images with different exposure) but I can't find any mention of in-camera composition of the final hdr - all sources just tell you to use an external software for the HDR composition. I'm not doubting you but this sounds like an undermarketed obscure feature - can you find any references for this feature?