Yes, it features moisture-resistant construction with leak-resistant seals throughout the lens barrel and a fluorine coating on the front element to repel water and fingerprints.
No, it does not have built-in optical stabilization (VC). It relies on Sony's In-Body Image Stabilization (IBIS) found in most modern Alpha series camera bodies.
Yes, it features a 67mm front filter thread, which is standardized across most of Tamron's Sony E-mount lineup, allowing you to share ND and CPL filters between lenses.
Absolutely. The 17mm wide end is perfect for handheld vlogging, and the RXD motor provides near-silent autofocus that won't be picked up by external microphones.