Download the official draw.io portable version from a trusted source, and carry your diagramming capabilities safely in your pocket.
Use Microsoft Remote Desktop to connect to your work PC that has Visio installed. From your USB drive, run the RDP client (which is truly portable). You are not carrying Visio; you are remotely controlling it. Microsoft Visio Portable Download
A: Use the web version of draw.io (diagrams.net) via a browser. No installation, no admin rights needed. Export as PDF or VSDX. Download the official draw