It's not as simple as this. It shouldn't be considering the second child armature at all in the character export.

Exporting with the bow rig selected causes the export to fail as the export also includes anything selected and it's not expecting to see another armature. Also it thinks the bow is then the preferred character armature so the export retarget generates a whole lot errors. (Testing for the object modifier doesn't fix this, it just stops the script crashing outright.)

Exporting without the bow rig selected works fine for just the character.

Are you intending to export just the character animation or the bow animation too?

Exporting with an accessory parented like this is not a use case I had considered, but it seems to me that exporting the accessory/bow as a separate accessory animation could also be useful. Though I would have to see how to put them back together in Unity to decide on the correct way to do that.

It's not as simple as this. It shouldn't be considering the second child armature at all in the character export.

Exporting with the bow rig selected causes the export to fail as the export also includes anything selected and it's not expecting to see another armature. Also it thinks the bow is then the preferred character armature so the export retarget generates a whole lot errors. (Testing for the object modifier doesn't fix this, it just stops the script crashing outright.)

I agree and this is what I am trying to achieve. My ticket description is kind of lacking so sorry for that, my goal is to be able to attach custom objects to rigified character's armature, which help make better animations and have better preview how the animation will play with other objects, but during export I am fine with the addon just ignoring them and exporting a character as usual, but right now it just crashes. To make it work like this I need to unparent all the custom objects to export a character.

Are you intending to export just the character animation or the bow animation too?

Exporting with an accessory parented like this is not a use case I had considered, but it seems to me that exporting the accessory/bow as a separate accessory animation could also be useful. Though I would have to see how to put them back together in Unity to decide on the correct way to do that.

I am trying to just export the character itself. Exporting it all together would be great, but I think having to export it separately isn't that big of a deal.