What you need to do is not think of the Outback Wilderness as a model on top of a basic Outback. Instead it really is more of a model on top of an Outback XT.
I go back to a question asked about the origin of the 2.4 liter Turbo 4.
Is the 2.4 Turbo motor imported as a single unit manufactured by Subaru in Japan?
Is the 2.4 Turbo built in the US based upon US/North American sourced parts of parts sourced from Japan?
If the answer to this question is yes to #2 - then it is not likely that the 2.4 Turbo will find a home under the hood of the Forester. Simply because the logistics of making the motor here and shipping it back to Japan is not viable. I do not think that the 2.4 Turbo is available outside of the US/North American markets. I don't think the Ascent or the Outback XTs are available outside of US and Canada...
If the answer to this question is yes to #1 - then it IS at least possible that the 2.4 Turbo could find a home under the hood of the Forester Wilderness. Of course, this then raises the other question about why it hasn't found a home under the hood of a Forester Sport XT or similar model.
As the current Forester is not really "gimped" in off-road situations (face it, it's never going to be a Jeep Wrangler competitor at Moab) and it has proven as a solid option for many "soft-roaders" (just like the n/a Outback and the Crosstrek, no matter which motor), there's not a lot of incentive for Subaru to put the turbo under the hood of the Forester. They've had 3 years of the SK generation to put the 2.4 under the hood - the same 3 years it's been in the Ascent; even if you just go for the first appearance of the XT Outback, it's been 2 years that could have found the engine in a Forester. Given how many threads and posts on here, as well as lamentations by car reviews and magazines and online blogs and so many other places, Subaru could have/should have/would have done this already. If anything, we may see it under the hood of the next generation (SL?) of the Forester which would be after 2023 model year.
As I said before - we'll just have to wait until more information s officially released by Subaru because everything else is just rumor, opinion, supposition and innuendo.