I'm guessing that this isn't a fully native gsm object - it is simply modelled in a 3d modelling software, most likely 3ds max / rhino / maya / blender, and then imported into archicad using an import plugin. if your goal is to use these objects just for visualization, i would recommend looking into rhino or blender. i would also suggest that you dont import these into archicad, because they will be high poly objects and it makes no sense to 'congest' your BIM model with such objects (looking good but containing very little data in terms of BIM).
if you use twinmotion, you can add high poly furniture there and it will work fine. I usually have placeholder objects in archicad, which I then hide when exporting to twinmotion. Alternatively, you can first sync them to TM, place the better quality models, then turn them off in the sequent syncs.
AC26 ARM //
MBP M2 Max //
Ryzen 2700x | GTX 1660ti //
UE5.1 | Twinmotion | Corona | Rhino