O'Neill is a high-motor edge defender with terrific play strength. He uses efficient hand work in tight quarters to work around blocks at the point of attack, but he lacks range in pursuit. As a pass rusher, he relies on effort and strength, with room for growth in his rush plan/execution. His lack of explosiveness and length caps his overall rush potential, though. O'Neill projects as a viable backup outside linebacker in an odd-front scheme and offers core special-teams value.
