Foreign investors in US real estate do not use GSEs to finance their purchase. However, the US tax payers largely do. The banks are not financing conforming mortgages as they originate the mortgages and sell to the GSEs. US banks are financing only the jumbo loans and by far mostly service their private clients. So, yes, the segment of the market where loan balance is non-conforming or purely cash based is less likely show sensitivity to the survival of GSEs. However, it would matter to real estate transactions that are financed for FHA or GSEs.
For an average American if you know when you want to buy or sell a house and the financing is not available to the buyer, it would impact the prices adversely. And which that, it affects consumer confidence and economy...
It doesn't really matter which state you are in.
The whole debate around whether there is enough private capital to take up the slack if GSEs were to no longer provide conforming mortgages to the housing financing market is what make the Corker bill hard to implement. Since the creation of the GSEs, conforming mortgages are provided by the GSEs, private capital can provide financing, but at what scale and at what price? Both (not enough capital, or higher interest rate ) would have adverse effect on housing prices.