Here are some ways to express a similar idea:
Using "Kung" (If)
* Kung ikaw ang bumati sa akin, ano ang sasabihin ko? (If you were to greet me, what would I say?)
* Kung ikaw ang magiging panauhin ko, ano ang dapat kong gawin? (If you were to be my guest, what should I do?)
Using "Ano kaya kung..." (What if...)
* Ano kaya kung ikaw ang magsabi ng "Maligayang pagdating"? (What if you were to say "Welcome"?)
* Ano kaya kung ikaw ang unang bumati sa akin? (What if you were the first one to greet me?)
Using "Paano kung..." (How about if...)
* Paano kung ikaw ang bumati sa akin? (How about if you were to greet me?)
* Paano kung ikaw ang magiging bisita ko? (How about if you were to be my guest?)
Using "Ipagpalagay na..." (Let's say...)
* Ipagpalagay na ikaw ang bumati sa akin, ano ang sasabihin ko? (Let's say you were to greet me, what would I say?)
* Ipagpalagay na ikaw ang magiging panauhin ko, ano ang dapat kong gawin? (Let's say you were to be my guest, what should I do?)
Remember that the best translation depends on the context and the specific idea you are trying to convey.