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I see from the post that you want to know if Mac OS 10.12 supports Wi-Fi Direct on your HP OfficeJet Mobile 250 printer. Don't worry I'll try my best to help you with this,
After reviewing your post, I believe it should support, only thing is you would need to connect your Mac to the printer through Wireless direct network.
To know more about Wi-Fi, please go through the link.
I hope this helps, let me know if you need any further assistance. I'll be more than happy to help.