After Effects (for the animated UI mockups) youtube tutorials :
(basics) Free After Effects Course - Beginner Infographics & Data Visualisation
How to create Animated UI mockup | After Effects
Create a 3D Mobile Phone App Promo | After Effects Tutorial
Rotato youtube tutorials : rotato.app (for the 3D videos / only for Mac users)
Create 3D Mockups using Adobe XD Plugin and Rotato | Adobe XD Tutorial
Animated 3D mockups in seconds - Rotato Adobe XD plugin
Mokup Frames youtube tutorials : mokupframes.com
Quickly Featuring your UI Design Animations with MokupFrames
Crypto, Figma plugin youtube tutorial (for recording Figma) : Crypto Password Protection
Figma Tutorial: Record your Figma prototype to a video file
Figma plugins (for the still images) :
youtube tutorials :
Mobile Mockup Presentations Made Easy with Artboard Studio
Figma mockup plugin Artboard Studio
How to Create Mockups using Figma Plugins