you are looking for a range of sounds depending on th sub-genre
electric piano
bass (fretless or similar)
saxes
trumpets
trombones
funky guitar (Scarbee funk guitarist should cover that)
appropriate styled/sampled drumkit
What do you use to make beats with???
Short answer is no plugins, but jazz records, or.....even sampling jazz from youtube.
If you want to do all of the creating what bandcoach said.
There used to tones of free good quality "sound fonts" with the needed sounds too.