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I have one in my bag of axle spares, and the maximum it could cover is 116mm over the outside of the fork ends.
I checked the two within arm's reach (Shimano enclosed cam and Miche X-Light) and they're both about 123 mm with the cam closed and a minimum 3 turns of thread engagement.
I reckon there's enough variation in front skewers that a rummage through an LBS parts bin might find one that will work.
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3 turns of thread engagement
You should be aiming for 10 turns (8mm on an M5 skewer). That takes you back down to the 117mm, i.e. 100 OLN and 8.5mm thick fork ends. Halo XL Allen key skewers are listed as 122mm max, so if your fork ends are 6mm or less thick they should work, in a limited sense. It's worth bearing in mind that Allen key skewers are even worse than QR skewers in terms of the disc brake wheel ejection issue referred to above, whereas track nuts are several times better than even a Shimano closed cam skewer.
gbj_tester
Ones which don't exist 🙂
There are plenty of 15×100 to 9×100 converters available because people wanted to put new wheels in common old forks. Your problem is that 9×110 is not common, yours is the first one I've come across. Boost hubs were designed to go in through-axle forks, and there were no legacy forks they'd go into even if there was a conversion axle since the disc line is not the same as old 9×100 and 20×110 hubs. All the 9mm through axles which might be the starting point for an alternative to a skinny 5mm skewer have the same problem as the skewers, they are designed for 100mm OLN hubs and will be too short for you. I have one in my bag of axle spares, and the maximum it could cover is 116mm over the outside of the fork ends.
In principle, the conversion kit I used was a tube, a length of studding and two track nuts. The last of these you can easily buy, but M9×1.0 studding is not anybody's idea of a stock item and again M9 front track hub axles are designed for 100mm OLN and won't stretch the extra 10mm.
You can buy M9×1.0 screws, so the bare minimum custom solution is a 14.9×109.5 rod with M9 female threads in each end, or the same with M9 male extensions each end to accept OTP track nuts.