If you're looking for a Rekordbox alternative, Fadr is worth a look. It's a collection of AI-based music tools geared for creative music production and DJing. With a vocal remover, song splitter, key/tempo/chords detector, remix maker and DJ controller, Fadr has a lot of tools to get songs uploaded, audio and MIDI files extracted and remixes and mashups created. It comes with two pricing tiers, so you can pick what works best for you.
Another option is RipX DAW, an AI music production tool that can perform advanced stem separation and editing. That's handy for DJs who want to dissect mixed audio into separate stems and then edit them note by note. RipX DAW runs on macOS and Windows, and you can try it for 21 days free, so it's a good option for producers and DJs who want to control audio at a fine-grained level.
If you're more interested in editing and manipulating audio samples, Samplab is a great tool. It's a polyphonic audio sample editor with the ability to adjust tempo and key, separate stems and export MIDI files. Samplab is available as a VST3 and AU plugin or desktop app, so it'll fit right in with your DAW, and you can try it for free to start.