Transferring defunct app which is not available in my country from wife's iphone to mine
I accidentally deleted an app from my iphone which is no longer supported by Apple and it says "This app is currently not available in your country or region" when I tried to airdrop it from my wife's iphone (which has this app). It does not appear on my App Store history as I had downloaded it when I had an Android phone previously. Can you help me transfer this app from my wife's iphone to mine?
iPhone 13 Pro, iOS 18