A while back I helped in creating Deloitte's Help Quest adventure game, designed to teach principles of being helpful.
I created the level environments in Unity using SYNTY asset packs, and helped setup the SYNTY character models with Mixamo animation. Occasionally creating custom prop assets in Blender to match the existing lowpoly style.
I also was in charge of creating the UI designs, using some assets from Layer Lab UI Kits.
I would also create custom 2D icons for props in Photoshop and Illustrator.