Hmm ...,
I'm just an (old-school) bog-amateur sax player. But - in addition to my amatuer 'Big Band' - I also play in an amateur Pop/Rock band together with a trumpet player. I've also considered various 'effects', including the Helicon Voicelive 3 and Boss VE20. But I decided on a much cheaper (and simpler) device that just allowed me to add some delay and reverb at live performances. Without any 'harmonies' or 'synthesized' sounds.
I have no idea about your ambitions or budget, but for me - just watching YouTube videos - the moments that a 'live' horn section steps on stage gives both visually and audibly a 'big boost' to any live concert. I'm not convinced that an 'audio-processed horn section' from 1 tenor sax would create the same 'boost'.
Just as a two examples, one from a Dutch Band that usually included a Tenor Sax and Trumpet player as the 'horn section', And the second one from a 'big budget' production by George Era. IMHO it's not so much about the 'size' of any horn section than can occasionally 'join in'. But mainly about the audio and visual 'boost' that they can give to any live concert. Just my humble opinion.
1 Dutch Band (with 1 tenor sax and 1 trumpet) - they come in towards the of this track.
View: https://youtu.be/4_ekENUlDgA?si=QmMJ34Cu0BMj4Ogw&t=6678
2 The 'Big Budget' concert by Georg Ezra
View: https://youtu.be/l1pxnZXvJkg?si=5f8Owx1iKSUqCBpL