Skill Link is generally preferred, due to its help in breaking subs and Sashes, plus Toucannon utilizes it well with moves like Fury Attack (Return is better though), Bullet Seed, and Rock Blast. Sheer Force doesn’t boost very many moves, with the physical ones being limited to Gunk Shot, Brick Break, and U-turn. It boosts Toucannon’s special moves (of which there are not many), and Toucannon is a lackluster special attacker. It works, but you would have to invest in Special Attack and use Choice Specs, making for a sadly narrow, unimaginative user of Sheer Force.
Overall, while it can catch an opponent by surprise, Skill Link is usually picked instead due to Bullet seed and Rock Blast being able to break Substitutes, Sashes and Sturdy, while Sheer Force doesn’t boost enough moves to make Toucannon very good with it.
Hope I helped!