How to assign a default context value in AR when the user select the BU through a Sanbox ?

SHow to assign a default context value in AR when the user select the BU through a Sanbox ?

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Hello

We have 2 Business Units one for USA and Mexico .

The users in Mexico is mandatory to capture some additional information on the AR invoice. however is requiered the user select the context value = Mexico.

I was wondering if it is possible to setup a personalization through a Sanbox to enable the Context value = Mexico when the user select the BU Mexico ?

I think maybe is possible to do it through the option