Unless you were like Masters or GM on console, honestly in like a month or two your aim will be fine for the hero pool you play, other than Zen really. That's if you play regularly. The biggest thing will be just finding a comfortable sensitivity for yourself and just relearning the game since you're getting back into it. Be prepared, you're probably going to place lower than you were on console, but you'll be at a significant advantage to the people around you because you will already have that built up game sense from your time on console.

Check out this video on the PSA method for finding your ideal sense. That's a really good place to start off, but you might change it in the future depending on what you play. I know when I started in OW, I began playing on a really low sense because I thought it would compensate for my lacking mechanical skills at the time (it doesn't, btw) and have changed it over time to suit my aim style and play style.