This is not realistic, but there are just so many great matches for trades between these two teams and since they are playing tonight I thought I would have some fun.
This "fantasy" trade assumes that Kane has a really small list of places (1 or 2) he wants to go with his full NMC and one of them is Toronto, putting Chicago in a poor negotiating position in terms of value. Hence, they create a package with multiple pieces that includes Kane to make the return look better overall.
The Leafs give up two of their better prospects in Hirvonen and Niemelä along with Roberston (who is a gamble due to his injuries), a late 1st and a potential second 1st if the Leafs make it to the SCF. Chicago would frame the trade as recieving two top prospects and two firsts, and two young NHL-capable players with upside (Abruzzese could step in for the rest of the season for Chicago). Whereas Toronto would say they gave up a first but didn't have to part with their two top prospects in Knies or Minten in exchange for a proven playoff difference maker in Kane, scoring depth for the playoffs in Domi, and upgrades to their D and bottom 6 with term in McCabe and Lafferty.
The resulting lineup is much deeper and provides more lineup flexibility with Domi able to slide to the wing in the top-6 or they could slide Kane down to play with Domi like they do in Chicago and have 3 stacked offensive lines. Lafferty's ability to play center and win faceoffs provides more bottom-6 flexibility as well. The Leafs powerplay should get a bump from having Kane on it. They could experiment with the 5 forward unit again or go with a more balanced PP1 and PP2 to create competition and drive results.
Holl and Kerfoot get shipped out to teams in the West to make the money work and recoup some draft capital. Teams may not be ideal. I went with Minnesota assuming they ship our Dumba and want a RHD replacement on the cheap (and Holl is from Minny) and KErfoot seems like the sort of depth that could help Seattle in the playoffs and somone they had interest in during the expansion draft. He is also somewhat local being from BC. But really they could go anywhere for any return.
I used CLB as the broker for double rention on Kane as the real money value is small and they have lots of cap space. I tossed in Nyquist as part of that deal as it is the sort of thing Dubas might do and has done with CLB previously (acquiring a LTIR player that may become available in the playoffs).