Source Wireframe Kit - Library of 537 blocks for desktop and mobile prototyping
Figma Super Tidy - Figma plugin to easily align, rename and reorder your frames
Form Wireframe Kit by InVision - A free wireframe kit from InVision
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Contra Wireframe Kit - Open source wireframe kit for design and prototyping 🚀
Easometric Figma Plugin - With Easometric it's really easy to create isometric layers.