Yes, You can connect Redmi Y2 with smart tv.
Yes, Redmi Y2 does have the EIS for the video recording.
Yes, Redmi Y2 does have the support for Miracast.
Yes, You can have 2 different WhatsApp account on Redmi Y2.
The Xiaomi Redmi Y2 is a slightly better attempt at a selfie-focused smartphone than the model it replaces. It has proven hardware that is capable of delivering a smooth user experience, plus MIUI 9.5 which has a lot of added features.