Surly Ogre thru axle fork options
A 12mm thru axle to 9mm thru bolt adapter (literally just a 100mm long tube that is 12mm OD and 9mm ID) can provide a strong, stiff, and tool-free interface, and I believe is available from the same source as the 12 to 5mm adapter you are considering. In my experience, thru bolts (e.g., the tool free version available from DT Swiss) are much stronger than a hollow 9mm axle with 5mm qr skewer (I have broken a few), and have every advantage of a thru axle.  This would allow you to use the Ogre fork, or any of a number of QR-style forks.