Memoji Ipad Mini IOS 13

Memoji and Animoji Stickers, for iPads that can run iPadOS, requires an iPad that has an A9 CPU or greater. The iPad Air 2 and iPad Mini 4 models ONLY have A8X and A8 CPUs, respectively, and are ineligible from getting the Memoji Sticker feature of iPadOS.

That and none of the more sophisticated FaceID cameras needed to use any of the Animoji features.

For very good, third party Memoji apps for yout iPad model, I recommend either Emoji Me or Your Avatar Creator.

My Memoji that I use here in these Apple product support communities was created by Emoji Me and modified using Pixelmator for iOS.

Good Luck to You!

How to use Memoji on your iPhone or iPad Pro - Apple Support

animoji require a face ID supporting ipad non of the minis are