real-time equalisation?

[Trebor]

… well I usually use Foobar player and mess around with the real-time EQ there and then just transfer the dB values over by eyeballing the Foobar EQ…

There are several free real-time equalizer plug-ins which work in Audacity on Windows …

How to make sax tone brighter with Audacity 2.3.2 Effect?

Yes, if you install a real-time equalizer plug-in into Audacity, e.g. https://www.voxengo.com/product/marvelgeq/ https://www.tokyodawn.net/tdr-nova/ which are free. (NB: Audacity only accepts 32-bit plug-ins even if your computer is 64-bit)