Commercial Animation Software

This list focuses on software used to make 2D character animation in motion design; there are other software programs like Cavalry that are more focused on procedural animation. Also, a shout out to Adobe Animate / Toon Boom and TV Paint, which I covered in TV animation software; however are used a lot in the commercial space as well.
(image above: Linn Fritz)
Adobe After Effects
A standard for commercial animation. Most freelance jobs assume you have it. Used for motion design, compositing, character rigging via plugins, and exporting Lottie animations for web and apps.

Where to learn
Ben Mariott - Amazing free tutorials for AE animation (also paid courses available)
Jake in Motion - Long time AE tutorial maker, this character rigging tutorial is great.
School of Motion - paid, and a widely used platform for learning motion design.
Motion Design School - Another great online course platform focused on motion animation.
Useful plugins
DUIK - free character rigging Free
Flow - My favourite After Effects Plugin, which lets you make custom eases very easily. Paid
Motion Tools - Super helpful collection of tools to help animating
Overlord - widely used plugin for transferring assets from Illustrator to AE
AeScripts - lots of useful plugins and scipts (mostly paid)

Rive
Interactive animation for apps and websites. Used by Duolingo, Figma, and lots of SaaS brands. Animations made in Rive can respond to user input in real time, which is something After Effects/Lottie can't do.
The free tier is generous, and the official tutorials are excellent.
Where to learn
School of Motion - again!
Rive official - great tutorials
Jake in Motion - again!