I could've sworn VC++6 had Intellisense. I'm not going to dig too far to confirm but Wikipedia seems to agree with me (https://en.wikipedia.org/wiki/Code_completion#Visual_Studio) - it's not a great reference but definitely implies that it was there:
> the Visual Basic versions of IntelliSense were always more robust and complete than the 5.0 and 6.0 (97 and 98 in the Visual Studio naming sequence) versions of Visual C++