Need help for a 'War of the Dual Successions!'

A little help, please!

I'm working on a war for an upcoming TL in which two internationally unpopular successions in two different large potential alternate nations drive both of those nations into an enormous, unwinnable (and mutually hypocritical) war.

I need to use dynastic marriages (and probably a fair amount of smallpox...) to create a situation wherein a much earlier analog to Phillip V is possible in the early days of the 17th century; i.e. one monarch - preferably a Hapsburg-Bourbon or vice versa - in position to inherit the thrones of France, Spain, and Portugal.

The pod can't be any before 1520 and the actual succession war needs to be begun by OTL's Thirty Years War, and preferably not much earlier.

I thought I had found a good lineage to work with, but then my eyes began to cloud as they do following any extensive family tree studying... I know it's possible but I need your help with all the births and deaths that must be tweaked...

And so you know the backup, the TL I'm working on has a pre-Columbian pod but no butterflies in the Old World until the 1520s. Spain has a slightly harder time colonizing the new world but not by much, and a little extra luck, good timing, gold, and a few more good men basically allow Suleiman to achieve all his campaign goals during his lifetime. Through ways I won't spoil a rather large new nation (centered predominantly around Poland if you must know) is about to grow slightly too large with one dynastic marriage (and one unfortunate death) too many. When it becomes clear that there will be two nigh invincible behemoths on the continent (Franco-Iberian and the Polish-oriented one I shan't name) dual succession wars are called just in time for the religious tension that caused the thirty years war in otl to boil over. It's essentially a WWI in the 17th Century, but is called the War of the Dual Successions as neither side wants the other to become so powerful.

It's a bloody draw, but one that completely changes the course of world history in surprising ways.

Anyway, now you have all you need. Someone please get me a(n) (un)lucky Franco-Iberian monarch and his ancestral family tree!
 
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