Corporate law

Hey,
There is no disadvantage in pursuing a certificate course. Law as a subject, the more you learn, the better you are. So, if you want to specialise in a particular area of law or if you want to build a career in a specific area of law, I think pursuing a certificate or diploma course in that area of law will provide you with the much needed insights as well as provide you with knowledge which would set you apart from your other colleagues. And coming to the best part about certificate course, they can be done together with the degree program that you are pursuing. So let's say you are enrolled in BALLB at NLSIU. A course on Mergers and Acquisitions is being offered by some Tier I Law firm. Mergers and Acquisitions being an important area of Corporate Law, it would provide you with practical insights and you can mention this course on your CV which would help you demonstrate your interest in Corporate law to the interviewer.

I think by better scope you mean better income, so here is the comparison:
Corporate law
According to the United States Bureau of Labour Statistics, the projected job growth for corporate lawyers is 6% (2014-2024) and their median annual salary is $ 1,15,000.
In India, after completing a course in corporate law, you can be hired by a business firm or a large MNC at a good salary package.
The starting salary depends on your skills and from which college you have completed your course. In general, you may get anywhere Rs. 25000 to 45000 per month. After some experience, you can easily get Rs. 50,000 to 1,00,000.
International trade law
According to the payscale.com, in 2016, international trade specialists made a median annual salary of $62,641 and the job growth is same as corporate lawyers.
In India, lawyers in this field are very less in number and this will give you the advantage to earn and in the beginning, you may earn from INR 40,000 to 60,000 per month and after some experience, it may go up to 15-20 LPA.
Salary packages shall vary on different factors like company, education, candidates skills, work experience, etc.
So which one has a better scope that you should decide based on your interests.

If you are interested in this field, then you must pass your class 12th or senior secondary examination with an aggregate of 45% from a recognized board or university. After fulfilling the above eligibility criteria, you can appear for the CLAT exam (common law admission test), conducted for the admission to the top government and private colleges in India. After successful clearing the exam, you may choose the course and specialized law branch of your choice.
Law courses in India:
There are various other law specialization courses that you can choose as per your interest these include:
B.A L.L.B: The B.A. LL.B is the most preferred choice of the law aspirants. This is an integrated course for the duration of 5 years. The students generally opt this course after completing their class 12th.
L.L.B.: L.L.B is also a 3 year course in law, you can go for this course after completing your graduation from a recognized board or university.
L.L.M: The L.L.M is a postgraduate course in law. The candidates are applicable for this course after completing B.A. L.L.B or L.L.M.
Some of the specialization courses that you can choose after your class 12th or graduation are follows:
Criminal Law
Civil Law
Corporate or business Law
Cyber Law
Administrative Law
Labour Law
Patent Law

Corporate Law is quite different from the Company Secretary but can always bring in value to ones profile. Both the fields offers bright career opportunities but requires a lot of dedication and Hard work, so if you plan to pursue the two courses then this would require perfection in managing the two courses simultaneously.
There are very few institutes in India offering Corporate Law, which is a sub domain of a broader Law discipline I.e. Company Law. Institutes like Indian Law institute, NALSAR University, Acharya Nagarjuna University and a few others offer Corporate law courses.
You can also refer to the following link:
http://tinyurl.com/2caocc9