Can a child AnimBP override an Animation Layer Interface layer implemented by its parent AnimBP?

Development Character & Animation
1

Hi, I’m trying to understand the expected behavior of Animation Layer Interfaces with inherited Animation Blueprints.

My setup is like this:

ALI_OverlayPose
 └─ OverlayPose layer


ABP_OverlayBase
 ├─ Parent: AnimInstance
 ├─ Implements: ALI_OverlayPose
 └─ OverlayPose layer
     └─ Base overlay state machine


ABP_SwordOverlay
 ├─ Parent: ABP_OverlayBase
 ├─ Also uses / inherits ALI_OverlayPose
 └─ I created a Sword-specific OverlayPose layer
     └─ Sword-specific state machine


ABP_BowOverlay
 ├─ Parent: ABP_OverlayBase
 ├─ Also uses / inherits ALI_OverlayPose
 └─ I created a Bow-specific OverlayPose layer
     └─ Bow-specific state machine

In my character Animation Blueprint, I call Link Anim Class Layers and pass ABP_SwordOverlay or ABP_BowOverlay depending on the equipped weapon.

I expected this:

Link Anim Class Layers → ABP_SwordOverlay
→ use ABP_SwordOverlay's OverlayPose layer
→ run the Sword-specific state machine

But what actually seems to happen is:

Link Anim Class Layers → ABP_SwordOverlay
→ the OverlayPose layer from ABP_OverlayBase still runs
→ the base overlay state machine is used instead of the Sword-specific one

So my question is:

Can a child Animation Blueprint override an Animation Layer Interface implementation from its parent Animation Blueprint?

Or is this not supported / not intended behavior?

From what I’m seeing, it looks like if the parent AnimBP already implements the Animation Layer Interface, the child AnimBP inherits that layer implementation, and creating a layer with the same interface in the child does not behave like overriding a normal Blueprint function.

Is the correct architecture to avoid implementing the Animation Layer Interface in the common base AnimBP, and instead do something like this?

ABP_OverlayCommonBase
 ├─ Parent: AnimInstance
 ├─ Does NOT implement ALI_OverlayPose
 ├─ Common variables
 ├─ Common functions
 └─ Common update logic only


ABP_SwordOverlay
 ├─ Parent: ABP_OverlayCommonBase
 ├─ Implements: ALI_OverlayPose
 └─ OverlayPose
     └─ Sword-specific state machine


ABP_BowOverlay
 ├─ Parent: ABP_OverlayCommonBase
 ├─ Implements: ALI_OverlayPose
 └─ OverlayPose
     └─ Bow-specific state machine

In other words, should the common base AnimBP avoid implementing the Animation Layer Interface if I want each weapon-specific AnimBP to have its own completely different state machine?