It took me more than 4 years to complete my engineering, how is it going to affect my admissions in B-Schools? But I also have experience of around 20 months.

It won't affect much. You need to prepare for that question well. Be honest in your answer, don't be defensive. I know many students who entered Joka after spending more than 4 years in Engineering. All the best.

It won't affect much if you justify it properly and show your work experience and strengths.