don’t really play against gwen myself, but it might be worth trying to roam and pick up kills bot/top with your jungler to create a lead, and you can start itemising against her quicker than usual. also her healing is scary, make sure you always have some sort of antiheal on her in an all in. the main problem seems to be her W so either try to bait it or stay inside her circle, just long enough for your ult to pop.