Yes, multiple computers will have different external IP Addresses.
Why on earth would you use the local ip instead of the external one for some service like vape
I searched a bit on the internet to find out what the heck is PojavLauncher and from what I see it is an android application that allows you to run Minecraft Java Edition on your cell phone.
And because Vape is in .exe this means that you will not be able to use vape in PojavLaucher (because...