OTL, Karl Peter Ulrich of Holstein was chosen as heir to the Russian throne in autumn 1742. The delegation wanting to have him become heir to Sweden arrived a few weeks later (October 1742). As he was already heir to Russia, this was scrapped.
So. What if it had been reversed. Say in 1739/1740 (shortly after his dad dies) the Swedes choose him as being heir to the throne. Elizabeth Petrovna's coup still takes place in December 1741. No way either Russia or Sweden would tolerate a personal union. So, who does Elizabeth name as her heir? Or does she bite the bullet and marry (I doubt she'd give up Alexei Razumovsky, but I don't see her marrying Aloysha without massively undermining her rule).
@alexmilman @Valena
So. What if it had been reversed. Say in 1739/1740 (shortly after his dad dies) the Swedes choose him as being heir to the throne. Elizabeth Petrovna's coup still takes place in December 1741. No way either Russia or Sweden would tolerate a personal union. So, who does Elizabeth name as her heir? Or does she bite the bullet and marry (I doubt she'd give up Alexei Razumovsky, but I don't see her marrying Aloysha without massively undermining her rule).
@alexmilman @Valena