The Margarethe I'm referring to is the daughter of Maximilian I and Marie, Duchess of Burgundy. Assume her mom still dies young and her younger brother, Franz, still dies in infancy/is stillborn.
Would Max start making plans to split the Empire and Burgundian inheritence? Or would he only decide that if/when Philipp ends up as heir to Spain? (the only three candidates I can find offered for Philipp OTL were Anne of York, Anne of Brittany and Juana of Castile, and if things in England go roughly as OTL then 1&2 move to unlikely; or if Edward V succeeds without incident then 2&3 become unlikely). And what happens if Philipp leaves minor aged kids when he dies? Who succeeds Maximilian? Philipp's eldest son? Or Friedrich* (male-Margarethe)?
And if the Empire and Burgundy are split between two collateral branches of the Habsburgs, how might this change things? And who might make a good match for Friedrich? A German? A Jagiellon? Some other foreigner?
Please discuss