It depends on how dynamic the UI will be.
Can you see any issues with this on either Electron or QT? At first glance it feels like both should ok.
I don't see any issues with implementing your idea using Qt and it's will absolutely certainly be using less CPU and RAM without any optimizations.
Yet IMHO there is good chance that if you stumble into some Qt / CMake / C++ issue then you gonna be wasting ten times more time on initial implementation. This is C++ for you. And this might kill your project before you even get to first stable version.
Qt widgets would likely be the fastest and lowest footprint. Though I'm not familiar enough to say exactly how you'd go about that.