They always have a schedule for this stuff, but Shang hasn't even been out for 3 weeks yet, so it may be another couple weeks before we see a trailer or anything. We did also just see the Nightwolf teaser shot, so maybe a trailer is in our near future.

I always thought the silence and wait had something to do with the large amount gear items they have to attach to the DLC characters, but I never knew about their working conditions. That's unfortunate, but hopefully they've already all sorted it out and can work in a healthy mental state.

My guess is that we'll get a gameplay trailer for Nightwolf by the end of this week, with an end-of-July release date. The usual schedule for DLC in the past few games is one per month. There's already assets and files for Nightwolf in the game with the last patch, and some claims on the Reddit that Nightwolf gear/skins are appearing from AI battles and the Shrine.