Easy Roam and eSIM

No, you don't need an eSIM for Easy Roam. It works on your current Koodo line and lets you use your plan's talk, text and data in Mexico for $18/day, only on the days you use your phone. There is also a Caribbean & Mexico 7 Day Pass for $50, so if you'll use your phone most days the pass works out cheaper. Text CAR7PASS to 7626 or add it in Self Serve before you leave https://www.koodomobile.com/easyroam

A travel eSIM from another provider is an option if you mostly need data. Keep data roaming off for the Koodo line though, and don't call, text or use data on it, otherwise that triggers Easy Roam for the day. Receiving texts is free.

Also, Just to confirm, are you on a Canada/US/Mexico plan? If so you don't need Easy Roam for Mexico at all https://www.koodomobile.com/en/help/traveling-with-your-canada-us-rate-plan