Firstly, I would try to stop mentally differentiating torches from the same region from each other, based on a color or design that was given a name, as Different.
An Indo gold, purple, green, fairy dust sparkle fart torch.... Are all Indo torches.
I've heard it regurgitated at nauseam as well that indos and aissies shouldn't touch. I have never found it to be an issue and see it, constantly.
Malaysian torches are the only ones I've had, that Generally that do not play nicely with others.
Outside of that, you'll just need to read the torches. Some torches of the same geographic region still don't like to be super close. Some want to be cuddled up. Read the torch behavior and adjust accordingly.