Yes, Samsung Galaxy S9 is a hybrid sim mobile phone. Means, you can easily use either 2 sim cards or 1 sim card & 1 MicroSD card. You can use up to 400 GB MicroSD card with the phone. Samsung Galaxy S9 also has OTG support.
Yes, Samsung Galaxy S9 does have the stereo speakers. One speaker is located at the earphone and another one is just beside the USB Type C port. These speakers are tuned by Harman which further increase the audio quality of the phone. It also has the Dolby Atmos support, which provides 360 degrees immersive sound effect.
Yes, Samsung Galaxy S9 does have the wireless charging support.
Yes, Samsung Galaxy S9 does have the 3.5 mm headphone jack.
Samsung Galaxy S9 box includes S9 mobile (with battery), sim ejector tool, earphone, USB power adapter, USB Type C Cable, Back Cover and ear plugs.
The Galaxy S9 may be failing to wow with the design but makes up for that with performance and new camera skills.