I'm tempted to say Crash and Spyro but I can't think of why Nintendo would want them. They have enough platformers.
Sonic maybe but Sega would have to be totally dead for that to happen.
Would have liked to seen Nintendo pick up TimeSplitters to give it a shoe in a genre it has no foothold in (Metroid is FPA) but no.
Frankly, Nintendo has enough neglicated IPs of it's own from Kid Icaris to Donkey Kong that they simply don't need to buy more.