I appreciate you asking about “portable Autodesk Inventor,” but I need to give you a clear and responsible answer upfront: there is no legitimate, legal “portable” version of Autodesk Inventor.
Features of Portable Autodesk Inventor
Performance: Inventor is a resource-intensive professional-grade mechanical design tool. Unofficial portable versions frequently crash, fail to load complex assemblies, or lack critical libraries required for simulation and rendering. Official Alternatives for Portability portable autodesk inventor
Autodesk Inventor does not have an official "portable" version that runs directly from a USB stick without installation Autodesk Design Review (portable versions exist for DWF