That does sound like a good idea... I'll go ahead and add it to my mod at some point soon 👍
For now, the workaround is to use /s (or /shout) to send the messages properly globally.
I'm currently thinking of adding a new command to replicate normal chatting behavior of only sending to your team. Do you have a better idea than /t (or /team)?
And Oarc, my mod basically had to entirely recreate chat by recording each message, and then overshadowed the real chat so it can print out its messages with the added modifications... I've got a remote interface specifically because I can't catch prints from other mods.
Two simple(ish) mods that make use of it is Complex Death Messages and Biter Memoirs. And then the specific luals annotation for the signature is https://github.com/PennyJim/better-chat/blob/772061f3b1552d2e97e7d8ca2d0dd3cf9b6df240/runtime/handle_messages.lua#L148-L162