you would have to look up in a different system what the business hours are in another country
Don’t you need to do this anyways? Different businesses open at different times. Different people work at different times. In some countries restaurants and shops tend to open relatively later and in some they open relatively earlier.
Really it just saves a step. From:
It is 12:00 here.
Is is 9:00 there.
Do they open at 9?
To:
Is is 12:00 here.
Do they open at 12?
Sure, step 3 can often be guessed. (It is highly likely that a business is open at 14:00 local time) But you still need to look up an exact number to convert from local time to target time. So instead you just look up when they open (or what time businesses are usually open in that place).