Exaples:

https://www.youtube.com/watch?v=J_6cZzjfjSs

https://www.youtube.com/watch?v=2yDVM77lGlM

https://www.youtube.com/watch?v=2UC_eRcu2CY

https://www.youtube.com/watch?v=N6EJzNneiMA

https://www.youtube.com/watch?v=K-Q642Ln_Dw

https://www.youtube.com/watch?v=i_0G6WPuss4

The older soundtracks were mostly 'tracker' files, which was a sort of middle-ground format where MIDI-like instructions would trigger real samples. To really capture the feel of that era you could get a tracker program (e.g. ModPlug, or OpenMPT ), load some instruments/samples into it, and get going. You can even open the old files (often in .UMX format) in some tracker programs to see how they were made.

But you can achieve much the same result with any DAW and any sampler VST providing you can get hold of some older samples. Unlike newer sampled instruments, tracker instruments would rarely have a separate sample for every note, perhaps only 2 or 3 per octave, and the resampling of the same samples to play different pitches is part of the distinctive timbre of the time.

I'm not aware of any VSTs that specifically set out to model old tracker sounds because there is no standard sample set or synthesis method that was in use; we would just load in whichever samples we had available.

Def has somekind of Phaser sound and 303 synths could do something like..The Main thing is too learn one SYNTH outside and out. IE like SERUM massive fm8 etc.