Chychrun would be the only rumoured, in-season trade that I would sacrifice a 1st/Amirov/etc. for. Otherwise, the Leafs shouldn't be expending those high-quality futures for lower priority needs (e.g. JT Miller).
But even still, as much as Chychrun would be a game-changer, I would be way more interested in pursuing Hampus Lindholm as a UFA. Muzzin has to go for either to fit, but he is more likely to waive his NTC in the summer to a competitive team than he would be to AZ in a Chychrun deal for instance.
Lindholm could be had for around 7x7 and it costs you no assets, plus double the term compared to Chychrun who needs a new mega deal at the same time as the Big 3.