On the run/walk/crouch walk animation, if you scroll down there is an “anim notifies” section (not sure of spelling). Move the animation to where the player’s foot hits the ground, then right click and select “New Notify”. Name the notify something like “PlayFootstepSound”. In the anim blueprint, you can now right click in the event graph and search for “PlayFootstepSound”. On the event, play your footstep sound 
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