I have a iPhone 13. I am in MX pretty much full time and currently carry my iPhone and a MX phone with MX carrier. Would it be possible to setup the dual sim functionality on my current phone?

Yes it certainly can.

Your phone can use 2x SIMs simultaneously.

This can be one nanoSIM + one eSIM.

OR 2x eSIMS.

Note that your 13 can NOT be “carrier locked.”

See more info in these articles:

Using Dual SIM with an eSIM - Apple Support

About eSIM on iPhone - Apple Support

Find wireless carriers and worldwide service providers that offer eSIM service - Apple Support

The iPhone 13 has one physical SIM slot and one eSIM.

Maybe I have too much blood in my caffeine system, but I don’t know what you mean by “MX”.

I assumed - perhaps incorrectly - “Mexico” … ???