700c touring/CX/gravnel wheels

I need some wheels for a bike that is going to mostly be doing adventury type stuff. I need to be able to get some 40mm tyres on so Ideally a inner rim width of around 20mm

tubeless ? axle type ? disc or rim ?

Bitex hubs to Kinlin TL-23 rims and get your local bike shop to make them up to spec.

Should have all the hub / axle options you could ever want.

sorry forgot to mention,
its for a surly crosscheck, so either 130 or 135mm spacing, rim brake,

Bitex hubs to Kinlin TL-23 rims and get your local bike shop to make them up to spec.

yeah this is the direction I was thinking of going but thought I would ask on here first

you don't need 20mm internal for 40mm tyres, standard specialized spec for their 42mm tyres on the globe series was IIRC an 18mm internal , I've been running 40mm folders on a set of Pro Lite Bortola which have a 17mm internal and are brilliant off road dicking around, no problems whatsoever even with a clydesdale like me on board.

Considering slightly narrower than what you initially asked for will open up the range of rim/hub combinations you can actually use in real world situations especially if you're not throwing yourself down mega rutted routes kamikaze style.
However, here's some older style Kinlins in a few different drillings that are 20mm https://www.ebay.co.uk/itm/PAIR-Kinlin-700C-ADHN-Black-Alloy-Rims-622-Vintage-32-36-40/153176027169?hash=item23aa00b021:g:cD8AAOSwMsJbl-VU
hub wise, it depends on how you see things and what your total all up might be, I run Dura Ace 7700 on my touring cum gravel/utility bike, just amazing long lasting in all weathers and easily serviceable but only up to 10 speed, the Ultegra 6500s were pretty damn good also.

If you were going to MTB/135 and no more than 10 at the back then Shimano LX is probably your best bet and not too costly.
luck hunting