If I want to invest in 2 mutual funds while investing in an ELSS, should I look for the sector diversification of both schemes, or should I make sure that they don’t have the same stocks?

Go for funds with a good long term track record and do not delve too much into sectoral allocations. At best go with fund house that have different approaches to things (one may be more process oriented and another more aggressive).

As long as they are multicap funds and have good fund managers give them time to perform. The fund manager has flexibility to change the allocation as they deem fit.

With ELSS you can’t anyway switch out before 3 years. Therefore, you can make a call on if the fund when this period is over.

More: ELSS Funds for 2018