I was looking for a free oscilloscope vst/au plug-in for quite a while and checked some blogs to find a decent one. Unfortunately none of the presented plug-ins ended up working out for me.
By chance I later found the MFreeFXBundle which also contains a very nice oscilloscope as well as 29 other completely free plug-ins. In return for signing up you can download these 30 free plug ins right away 🙂
Now I really like using this free oscilloscope plug in for sound design and synthesis purposes.
I have no affiliation with meldaproductions btw haha just felt like after searching for a while would be nice to share it.
Cheers!
https://www.meldaproduction.com/MFreeFXBundle

Amazing Free plug-in collection from Meldaproductions