If I wanted to place two stones in a corner and then play away, what placement would maximize the corner as unsettled? In other words, if my plan was to play two stones in a corner and make it as hard as possible for my opponent to feel their stones were alive or safe, forcing them to play the maximum amount of stones there to feel they had the corner.
For example 3-3 and 5-5.
People stronger than me have said that if you want to make an optimal position for yourself with only 2 stones anywhere on the board, it would be 4-3 and 3-5 stones. Not only it’s super strong position and should be always guaranteed to be alive (unless you let your opponent to play free moves against it) but it’s also (usually) granting you nice amount of territory in the corner AND it has good potential to grow toward the sides.
So i would go with that as my guess ^^
Bit more about enclosures https://senseis.xmp.net/?Shimari
I’m not really clear on exactly what the question is. Do you want to make a corner that’s as hard to invade as possible? If so, the 3-4 5-3 enclosure is the most territory-oriented enclosure that shows up regularly in games. Basically every other common enclosure can be invaded in some manner.
That being said, with a 3-4 5-3 enclosure, it’s pretty easy to attack and live on the side, so long as there’s some space to work with. The other player can just attach to the 3-4 stone, either on the outside or underneath, and have enough to make something that’s alive.
Just play one stone at the 3-3 point.
You could place a stone at the 3-4 point and one at the 4-3 point. The issue is that the gain from the second stone is not worth the investment. Same for a 3-3 and 5-4 combo.
Other combinations (starting with 3-4 and 5-3) will usually leave enough room for the opponent to feel safe (see the link posted by @_KoBa)
btw it’s not clear to me what you mean by “maximize the corner as unsettled”. I am responding to your second sentence.
Are you talking about invasions?
Has your opponent already made some move in that corner? Which moves?
This can lead to many different answers. 
Thanks for all the responses. It’s been useful. What I was experimenting with was making a few moves in a corner that I never intended to actually “own”… so my two stones were placed in a way that required the maximum responses for my opponent to feel “safe” or like they owns that corner. Many of the ideas here influenced my decision on how to work this strategy. Again, thank you all.