Competition law internship with Sarvada Legal or international trade law internship with Tier 1 firm? Please help. Interests lean towards comp law, but will tier 1 tag help the CV more?

Go for Competition Law✌️

DSK legal is not tier 1

I would've said that even generally, a competition law internship at a good T2 would be more impactful than a trade internship at a T1. And since you aren't interested in trade, I'd say comp at Sarvada is the obvious choice.
Anyway, the only T1 with a trade practice is Luthra, and haven't heard great things about them of late.

What t 1 firm does trade law?

Have heard good things about Sarvada’s trade law practice as well. Mr. Seetharaman heads the practice. He is renowned in the circle.