There is not hard and fast rule in terms of experience.
-Under 4 years of industry experience + 2 summers worth of internship experience (did more in 3 months than i did in 6 months as a ful time employee because I only had so much time), very average grades, but extensive and very experience-filled projects over those years for a few fortune 25 companies.
-Applied online for MBB, currently in last stages hoping to make it through
-Also had a lot of extracurricular activites and informal leadership experience
Disclaimer: For me this experience -from what it sounds like - is pretty uncommon and it looks like I had the Grace of God making it this far, but maybe a data point that applying online soley might work and that if you have the experience and can display the proper characteristics, then there's always a slight chance?
-They don't care about grades for experienced hires, they care about your fit, ability to learn, problem solve and display their characterstics they look for
-Sell yourself = Strong commuincator + Genuine and legitimate qualification + relentless pursuit to either make it or gain the experiences necesarry to qualify
-I would defintely continue to try and network and reach out for referrals and grow your chances in the best ways possible
Maybe that's encouraging?