I'm having the same problem as you under MacOS 12.3. I used the following method to find out that there are garbled codes in the memory stick hardware information of macOS obtained by OCS Inventory NG Agent, and if I change these garbled messages to normal text, it can be imported normally. So I guess there is a bug in the current Agent to get the system information of macOS.
The procedure I used to find the problem.
1, run the Agent command to export a local asset file.
Open a command line console window and run the following command
sudo . /ocsinventory-agent -local=/tmp
2, open the .ocs file under /tmp with a text editor that supports xml format (e.g. BBEdit). The editor should indicate that there is an error in the format of the xml file, and you can locate the error line in the xml based on the error message in the Agent's log on your computer.