Unfortunately, the Server doesn't send any information about other players' inventories to the Client, therefore it's impossible to show it in the Replay.
Theoretically, it would be possible to show the recording player's inventory, but the ReplayMod tries to treat every player the same, and we do not plan on changing that.
Thanks for your feedback!
I made the same suggestion some time ago but the replay mod is not meant to do that
When i need such a shot i usually record both externally with a screen capture software and internally with the replay mod, then i mix the video together in After Effects using masks, it's quite a pain to synchronize the time and to manually change the masks when necessary but it works for now