How to build estate building that requires being a military administration

I am the Chinese hegemon and I want to build an estate building but can't as I am not a military administration. Is there a way for me to achieve this without too much hassle? this is iron man without mods.

I could think of making my family member heir a military governor inherit my estate and give my title to someone not of my dynasty(ie using matrilineal marriage). afterwards press my claim but not sure if that would work. also does anyone know if I can change back as soon as the first level of the building is built? or do I need to wait for all 4 levels to finish building before becoming hegemon again?

What are other ways of doing it?

I could also think of going into division era but not sure what's gonna happen with my European lands. I would prefer not having to war for them all over again.

There are many questions like in the event of a division do I keep my holdings or do I lose all holdings?