Anim To Sprite supports capturing NiagaraSystems partially.

Limitations

Input

NiagaraSystems for ATS need these conditions:

• Emitters need to be deterministic (fixed random seed)
• Emitters need to be CPU sim
• Materials should be opaque or masked, and its color is output to BaseColor
• NiagaraComponent needs to be attached to an Actor
  • Engine-provided Notifies in AnimComposite does not work for this.
  • ATS provides an alternative for this

Output

The same spec as those without NiagaraSystems. It means:

• Sprites have Colors/Masks and Normals (no alpha/add blend)
• Lit

How to setup

NiagaraSystem and material

NiagaraSystem needs to be deterministic.
Check "Determinism" in emitter properties.

Blendmode of materials for renderer needs to be Opaque or Masked.
BaseColor needs to be connected.

ActorBP and Capture

NiagaraOnly Actor

Attach NiagaraComponent to plain ActorBP.

Since it doesn't have Skeletal animation, the length of animation needs to be set explicitly.

Character-Attached

Attach NiagaraComponent to SkeletalMeshComponent then it will follow skeletal mesh animations.

If you don't want Niagara effect to be always shown, uncheck "Auto Activate" and set some ComponentTag.

Then use AnimNotify_ActivateNS to turn on and off it (in AnimComposite or AnimSequence).