diff --git a/scripts/addons_core/io_scene_fbx/export_fbx_bin.py b/scripts/addons_core/io_scene_fbx/export_fbx_bin.py
index 4641368ffb2..7f1e6bfea71 100644
--- a/scripts/addons_core/io_scene_fbx/export_fbx_bin.py
+++ b/scripts/addons_core/io_scene_fbx/export_fbx_bin.py
@@ -2491,16 +2491,25 @@ def fbx_animations(scene_data):
 
     # All actions.
     if scene_data.settings.bake_anim_use_all_actions:
-        def validate_actions(act, path_resolve):
-            for fc in act.fcurves:
-                data_path = fc.data_path
-                if fc.array_index:
-                    data_path = data_path + "[%d]" % fc.array_index
-                try:
-                    path_resolve(data_path)
-                except ValueError:
-                    return False  # Invalid.
-            return True  # Valid.
+        def find_validate_action_slot(act, path_resolve) -> bpy.types.ActionSlot | None:
+            for layer in act.layers:
+                for strip in layer.strips:
+                    for channelbag in strip.channelbags:
+                        if not channelbag.fcurves:
+                            # Do not export empty Channelbags.
+                            continue
+                        for fc in channelbag.fcurves:
+                            data_path = fc.data_path
+                            if fc.array_index:
+                                data_path = data_path + "[%d]" % fc.array_index
+                            try:
+                                path_resolve(data_path)
+                            except ValueError:
+                                break  # Invalid, go to next strip.
+                        else:
+                            # Did not 'break', so all F-Curves are valid.
+                            return channelbag.slot
+            return None  # Found nothing to return.
 
         def restore_object(ob_to, ob_from):
             # Restore org state of object (ugh :/ ).
@@ -2540,14 +2549,20 @@ def fbx_animations(scene_data):
             pbones_matrices = [pbo.matrix_basis.copy() for pbo in ob.pose.bones] if ob.type == 'ARMATURE' else ...
 
             org_act = ob.animation_data.action
+            org_act_slot = ob.animation_data.action_slot
             path_resolve = ob.path_resolve
 
             for act in bpy.data.actions:
                 # For now, *all* paths in the action must be valid for the object, to validate the action.
                 # Unless that action was already assigned to the object!
-                if act != org_act and not validate_actions(act, path_resolve):
+                if act == org_act:
+                    act_slot = org_act_slot
+                else:
+                    act_slot = find_validate_action_slot(act, path_resolve)
+                if not act_slot:
                     continue
                 ob.animation_data.action = act
+                ob.animation_data.action_slot = act_slot
                 frame_start, frame_end = act.frame_range  # sic!
                 add_anim(animations, animated,
                          fbx_animations_do(scene_data, (ob, act), frame_start, frame_end, True,
@@ -2557,6 +2572,7 @@ def fbx_animations(scene_data):
                     for pbo, mat in zip(ob.pose.bones, pbones_matrices):
                         pbo.matrix_basis = mat.copy()
                 ob.animation_data.action = org_act
+                ob.animation_data.action_slot = org_act_slot
                 restore_object(ob, ob_copy)
                 scene.frame_set(scene.frame_current, subframe=0.0)
 
@@ -2564,6 +2580,7 @@ def fbx_animations(scene_data):
                 for pbo, mat in zip(ob.pose.bones, pbones_matrices):
                     pbo.matrix_basis = mat.copy()
             ob.animation_data.action = org_act
+            ob.animation_data.action_slot = org_act_slot
 
             bpy.data.objects.remove(ob_copy)
             scene.frame_set(scene.frame_current, subframe=0.0)
diff --git a/scripts/addons_core/io_scene_fbx/import_fbx.py b/scripts/addons_core/io_scene_fbx/import_fbx.py
index e86a781527d..b48a2456e75 100644
--- a/scripts/addons_core/io_scene_fbx/import_fbx.py
+++ b/scripts/addons_core/io_scene_fbx/import_fbx.py
@@ -17,6 +17,7 @@ if "bpy" in locals():
 import bpy
 from bpy.app.translations import pgettext_tip as tip_
 from mathutils import Matrix, Euler, Vector, Quaternion
+from bpy_extras import anim_utils
 
 # Also imported in .fbx_utils, so importing here is unlikely to further affect Blender startup time.
 import numpy as np
@@ -893,10 +894,10 @@ def blen_store_keyframes_multi(fbx_key_times, fcurve_and_key_values_pairs, blen_
         blen_fcurve.update()
 
 
-def blen_read_animations_action_item(action, item, cnodes, fps, anim_offset, global_scale, shape_key_deforms,
+def blen_read_animations_action_item(channelbag, item, cnodes, fps, anim_offset, global_scale, shape_key_deforms,
                                      fbx_ktime):
     """
-    'Bake' loc/rot/scale into the action,
+    'Bake' loc/rot/scale into the channelbag,
     taking any pre_ and post_ matrix into account to transform from fbx into blender space.
     """
     from bpy.types import ShapeKey, Material, Camera
@@ -948,7 +949,7 @@ def blen_read_animations_action_item(action, item, cnodes, fps, anim_offset, glo
         else:  # Euler
             props[1] = (bl_obj.path_from_id("rotation_euler"), 3, grpname or "Euler Rotation")
 
-    blen_curves = [action.fcurves.new(prop, index=channel, action_group=grpname)
+    blen_curves = [channelbag.fcurves.new(prop, index=channel, group_name=grpname)
                    for prop, nbr_channels, grpname in props for channel in range(nbr_channels)]
 
     if isinstance(item, Material):
@@ -1115,7 +1116,8 @@ def blen_read_animations(fbx_tmpl_astack, fbx_tmpl_alayer, stacks, scene, anim_o
                     id_data.animation_data.action_slot = action.slots[0]
 
                 # And actually populate the action!
-                blen_read_animations_action_item(action, item, cnodes, scene.render.fps, anim_offset, global_scale,
+                channelbag = anim_utils.action_ensure_channelbag_for_slot(action, action.slots[0])
+                blen_read_animations_action_item(channelbag, item, cnodes, scene.render.fps, anim_offset, global_scale,
                                                  shape_key_values, fbx_ktime)
 
     # If the minimum/maximum animated value is outside the slider range of the shape key, attempt to expand the slider