Slapping a Genesis soundfont into a modern trap beat won't automatically make it retro. You need technique.
Modern producers love chorus effects. The Genesis had almost no reverb or chorus built-in. If you add lush Valhalla reverb to a Genesis bass, it destroys the illusion. Instead, use short, gritty delays (like a Boss DD-2 pedal) or Reverb set to "Spring" or "Small Room." sega genesis soundfonts
Because Yuzo Koshiro (composer for Streets of Rage) is a god, several fan-made soundfonts isolate his instruments. Search for "Yuzo Koshiro Soundfont." It contains the specific saw waves and punchy kicks used in Streets of Rage 2—one of the most sampled video game soundtracks in electronic music history. Slapping a Genesis soundfont into a modern trap