I can already see a marriage that would be just made in order to have a powerful child

Water is the strongest by far

@Mr.Interest that's literally what endeavour from my hero academia did

Air and id find a water one,and child n stuff then id get the child to get married to an earth one then the grandchild with a fire one and make the strongest person

If a child's elemental power is that of the most powerful parent, then just have a kid with someone as powerful as you are to give your child dual elements.

I'm gonna be an Earthbender

Can we turn into our elements also? Kinda like a logia from one piece?

No.13Kid No only manipulate or generate in the case of Fire Elemental Humans.

Earth is by far the most versatile of these options

And if both elementals were equally skilled? What happens then