The Alembic, Collada, and USD im/exporters are implemented in C++. This means that they’re only exposed as an operator (bpy.ops.wm.alembic_import()
for example).
The good news is that all operators can be introspected directly, rather than having to through bpy.types.XXX_OT_yyy
classes:
>>> rna_type = bpy.ops.wm.alembic_export.get_rna_type()
>>> list(rna_type.properties)
[<bpy_struct, PointerProperty("rna_type") at 0x00007FF6C4EE4710>,
<bpy_struct, StringProperty("filepath") at 0x0000021A6CCB3628>,
<bpy_struct, BoolProperty("check_existing") at 0x0000021A6CCB2BE8>,
<bpy_struct, BoolProperty("filter_blender") at 0x0000021A6CCB25F8>,
<bpy_struct, BoolProperty("filter_backup") at 0x0000021A6CCB2728>,
<bpy_struct, BoolProperty("filter_image") at 0x0000021A6CCB2D18>,
<bpy_struct, BoolProperty("filter_movie") at 0x0000021A6CCB2988>,
<bpy_struct, BoolProperty("filter_python") at 0x0000021A6CCB2AB8>,
<bpy_struct, BoolProperty("filter_font") at 0x0000021A6CCA7FB8>,
<bpy_struct, BoolProperty("filter_sound") at 0x0000021A6CCA5628>,
<bpy_struct, BoolProperty("filter_text") at 0x0000021A6CCA3AD8>,
<bpy_struct, BoolProperty("filter_archive") at 0x0000021A6CCA7638>,
<bpy_struct, BoolProperty("filter_btx") at 0x0000021A6CCA7768>,
<bpy_struct, BoolProperty("filter_collada") at 0x0000021A6CCA4588>,
<bpy_struct, BoolProperty("filter_alembic") at 0x0000021A6CCA4458>,
<bpy_struct, BoolProperty("filter_usd") at 0x0000021A6CCA5038>,
<bpy_struct, BoolProperty("filter_volume") at 0x0000021A6CCA7508>,
<bpy_struct, BoolProperty("filter_folder") at 0x0000021A6CCA46B8>,
<bpy_struct, BoolProperty("filter_blenlib") at 0x0000021A6CCA6A58>,
<bpy_struct, IntProperty("filemode") at 0x0000021A6CC915B8>,
<bpy_struct, EnumProperty("display_type") at 0x0000021A6CCB4CA8>,
<bpy_struct, EnumProperty("sort_method") at 0x0000021A6CCB5C68>,
<bpy_struct, IntProperty("start") at 0x0000021A6CC91318>,
<bpy_struct, IntProperty("end") at 0x0000021A6CC92038>,
<bpy_struct, IntProperty("xsamples") at 0x0000021A6CC92C08>,
<bpy_struct, IntProperty("gsamples") at 0x0000021A6CC91708>,
<bpy_struct, FloatProperty("sh_open") at 0x0000021A6CC909E8>,
<bpy_struct, FloatProperty("sh_close") at 0x0000021A6CC91858>,
<bpy_struct, BoolProperty("selected") at 0x0000021A6CCA5758>,
<bpy_struct, BoolProperty("renderable_only") at 0x0000021A6CCA4F08>,
<bpy_struct, BoolProperty("visible_objects_only") at 0x0000021A6CCA47E8>,
<bpy_struct, BoolProperty("flatten") at 0x0000021A6CCA79C8>,
<bpy_struct, BoolProperty("uvs") at 0x0000021A6CCA41F8>,
<bpy_struct, BoolProperty("packuv") at 0x0000021A6CCA6928>,
<bpy_struct, BoolProperty("normals") at 0x0000021A6CCA3C08>,
<bpy_struct, BoolProperty("vcolors") at 0x0000021A6CCA7E88>,
<bpy_struct, BoolProperty("orcos") at 0x0000021A6CCA5168>,
<bpy_struct, BoolProperty("face_sets") at 0x0000021A6CCA4918>,
<bpy_struct, BoolProperty("subdiv_schema") at 0x0000021A6CCA6338>,
<bpy_struct, BoolProperty("apply_subdiv") at 0x0000021A6CCA4CA8>,
<bpy_struct, BoolProperty("curves_as_mesh") at 0x0000021A6CCA7AF8>,
<bpy_struct, BoolProperty("use_instancing") at 0x0000021A6CCA5D48>,
<bpy_struct, FloatProperty("global_scale") at 0x0000021A6CC92D58>,
<bpy_struct, BoolProperty("triangulate") at 0x0000021A6CCA80E8>,
<bpy_struct, EnumProperty("quad_method") at 0x0000021A6CCB3988>,
<bpy_struct, EnumProperty("ngon_method") at 0x0000021A6CCB5D88>,
<bpy_struct, BoolProperty("export_hair") at 0x0000021A6CCA4A48>,
<bpy_struct, BoolProperty("export_particles") at 0x0000021A6CCA7898>,
<bpy_struct, BoolProperty("export_custom_properties") at 0x0000021A6CCA4328>,
<bpy_struct, BoolProperty("as_background_job") at 0x0000021A6CCA6598>,
<bpy_struct, BoolProperty("init_scene_frame_range") at 0x0000021A6CCA4B78>]