Yes, It will be an issue, if you get a job and are unable to produce it.
It is important to have the semester wise/ consolidated marks sheets for Government Jobs and even private jobs.
Most jobs have the basic cut off of 'AN AGGREGATE of 55% or 60%' in the BSc, B.E or B.Tech etc advertised.
The semster wise markssheet also plays an important role when the average marks scored is questioned or rounded to a whole number (avioding decimal)
Right now, if you have to, you can apply for the government jobs/ competitive exams and prepare for the written tests etc. THese will be needed at the time of document verification wherein your ID proofs, education etc will be scrutinized in detail before allocating the job.
Please apply and in the mean while you can get the duplicate copies of the semseter wise marksheets.
Please visit the university website under whose auspices your engineering college falls under. There would be guidance to applying for duplicate marksheet. A form would have to be filled and a pre-agreed fee would have to be paid.
You can also draft a letter to the Registrar of the university explaining the service you need and enclose copies of your degree certificate, the university roll numbers and or hall ticket for the exams etc.
If you have any issues, you can approach the university office or the college from which you graduated by phone, mail or in person OR post a reply with your university and college details, one of us can help you out.