Keyshape is described as 'Create animated vector graphics. Keyshape is a 2D vector graphics and animation software. It combines drawing tools with animation tools in a single application' and is an app in the Photos & Graphics category. There are seven alternatives to Keyshape for a variety of platforms, including Mac, Online / Web-based, Windows, Linux and Self-Hosted solutions. The best alternative is Google Web Designer, which is free. Other great apps like Keyshape are Rive (Free Personal), Saola Animate (Paid), Hype (Paid) and SVG Flipbook (Freemium, Open Source).
Saola Animate is an ultimate tool to create HTML5 animations and interactive web content. Besides exporting to HTML5 output, the release of the latest version - Saola Animate 3.0 - allows you to export projects to video formats for demonstration purposes.
SVG Flipbook runs next to your SVG editor and lets you animate your creation. Each layer in your SVG becomes one frame. You can use whatever SVG editor you like. Inkscape and Illustrator both work great.