WI: Leopold Johann, son of Karl VI, survives

[Valena]

A small idea I've pondered on fai.org.ru while the website was down and posting it here.
In OTL Leopold Johann was born in April 1716 and died in November of the same year.
In a TL where he lives at least to the age of 40, that is to 1756 (being a mediocre ruler like his maternal cousins Peter II of Russia/Anton Ulrich of Brunswick), there are a few questions:
1. Who may he marry?
2. Who would his sisters marry, if Maria Theresia is not a heiress anymore?

 

[Emperor Constantine]

Had a really good discussion on this about a year ago, here's the link: https://www.alternatehistory.com/forum/threads/holy-roman-emperor-charles-vi-has-a-son.412263/

 

[Jonathan]

1. Who may he marry?
2. Who would his sisters marry, if Maria Theresia is not a heiress anymore?

1) potential brides:
Maria Amalia of Saxony
Elisabeth Theresa, OTL Queen of Sardinia
Louise Diane d'Orléans
María Ana Victoria, Infante of Spain and OTL Queen of Portugal

Interesting Prussian Princesses:
Philippine Charlotte, OTL Duchess of Brunswick-Wolfenbüttel
Sophia Dorothea, OTL Margravine of Schwedt
Luise Ulrike, OTL Queen of Sweden

Without being seen as a heir she could marry any head of state.

 

[Valena]

On the Russian forum I used "Leopold II" + Maria Amalia" & Maria Theresia + Carlos III of Naples, but then I thought about plausibility of this, and after reading the thread Constantine provided the link to it looks like implausible arrangement.