Enabling Intellihide on multiple displays is convenient because the taskbar appears on the display with inactive windows, but it is inconvenient because some boxes appear only on the primary monitor.
In particular, the lack of display of Input Method degrades the experience of users whose language requires it.
I'm responding from smartphone in respect of input indicator. Please check out the following in Settings. Go to Region and Language and then click on the Options button. See if there is an option similar to "Show in Tray". If it does, please let me know as I will need to modify the unofficial manual for Zorin 15 as it looks like I omitted this in error.