I am looking at a rear wheel replacement. I have a Scott Scale 980 with a standard wheel on the rear. Will I need a longer freehub to interface with the wide 12 speed cassette? Or are there general standard wheels that are compatible?
There are 3 standards of hub interfaces in modern MTBs. Which one you need is determined by the cassette you want to use:
Shimano HG: (sometimes called Shimano Standard or 11-speed hub) fits Shimano/SRAM cassettes up to 11-speed and SRAM SX/NX Eagle 12-speed cassettes
Shimano Micro Spline: All Shimano 12-speed cassettes
SRAM XD: SRAM GX/X01/XX1/X0/XX Eagle 12-speed cassettes
The Scott Scale 980 comes stock with a rear hub that is a 5mm QR (Quick Release skewer) with an over-lock-nut (OLD) of 142mm. This is a NON-boost hub (boost is 148mm OLD). The freehub body is a Shimano Microspline which is compatible with the Shimano Deore M6100 12 speed drivetrain.
Thus, when you shop for a rear wheel replacement (the wheels are 29ers or 622 in ETRTO), you'll require the hub to be the 142mm OLD with QR skewer and spec'd with a Microspline freehub body to fit the current Shimano 12 speed cassette.