TF2 has nice stylized models, but IMO the in game graphics are dated and not particularly special compared to newer genre examples like Overwatch, Splatoon, or Destiny.
All 3 examples here are excellent but I want to say I know a lot of people hate on Destiny but the art direction, environmental art, creature design is all magical in terms of tech and results. Honestly feels like concept art brought to life and anyone dismissing it and not even giving it a chance just are missing out on some seriously impressive visuals resting perfectly between realistic and stylistic.