not sure how this would work, interweave messages from both chats? But that will be really confusing unless you used the reply/answer function. But even then for me at least it would be really confusing to have two chat history intertwined with each other. like I asked a question some time ago in the one chat and not the messages of the other chat would show up right beneath my message and look like answers to my message at first glance.
A possibility to get things known beyond theory, is by getting involved, good master. If good master would try to start to sort up topics here in the forum, he would get such well known in short time. Simple merge is a very common tool, and usually the new build up of the merged chat is just by new topic/chat id (single message might still carry their original subject, which might be useful for detail investigations later. A small sign * that gives idea of a “merged” message, might be another help, if wishing)
How should the messages be arranged in time?
Let’s assume two groups will be merged into a new group.
In what order should messages be displayed that were written to different users in different groups at the same time?