What is the right choice to use between a Bitcoin payment processor and an exchange wallet, if it so happens that I find myself in a new country or region that is far from the familiarity of language, the regular dress codes and services I once enjoyed ?
What's the best choice between a BTC payment processor and an exchange wallet to use for a migrant?
Your question is little unclear to me but from what I get, you want to choose between a bitcoin non-custodial wallet and an exchange.
So whatever the reason may be, the right choice would always be to use a non-custodial wallet.
Exchanges cannot be trusted as we have seen large exchanges collapse previously.