Recruiter here. I'd leave it on, keep things positive when discussing, and own the situation as a learning experience. The risk of leaving it off is much greater to bite you down the road, and your honest explanation should show a level of maturity.

In a few years, you can probably remove it safely from the résumé and LinkedIn.

I would leave it on. Keep it professional and leave it in good terms with the current company.

You can easily explain that job did not fit you and you are always looking for the best in your career.