New Trend ? Offlane Void ? Any thoughts ?

I've seen a lot of mid Void, which in my opinion works better: much like a mid SF or Naga, it works as a "side carry" getting more levels than farm. Before reaching the later stages of the game he only works as an initiator and deals decent damage, but if the game drags long enough he can outcarry the majority of Heroes (including your team's carry).

About the item build, people usually go for an optional Hand of Midas, then Power Treads and Mask of Madness so they're sure they will be able to kill at least one enemy inside the Chrono. Then, Aghanim's Scepter is the best decision if your team has many teamfight ultimates, while the Black King Bar prevents the enemies from affecting him and is one of the most common pickups for him. In the late game, Daedalus and Mjollnir are the usual damage items for him.

I don't think off-lane Void is a good idea (your farm will be really lackluster and you're not ensured a quick level 6 versus most of the trilanes), but if I had to play it I'd probably go for a quick Bottle into Power Treads, maybe taking a Morbid Mask before completing Treads to go jungle farm. My build would most likely be Bottle, Power Treads, optional Mask of Madness if not underlevelled/underfarmed and then probably an Aghanim's Scepter, after which the Black King Bar would be kind of mandatory. As for the skill build, going 2-2-1-1 by level 6 is my favourite setup for now, maxing out Time Walk first, then Time Lock and finally Backtrack.