If the official trials aren't enough, several "freemium" and open-source tools offer similar functionality and even support for existing Pencil Project
Vectr is a free, web-based vector graphics editor that can be used to create diagrams, illustrations, and more. free visio link
For occasional Visio work, diagrams.net is the most generous free option—no sign‑up required and unlimited file size. If the official trials aren't enough, several "freemium"