Is there a way to chose NOT to export the BPM for RekordBox Analysed tracks?

No. Why would you want to do that?

Im a drum and bass DJ and want to Analise my tracks but dont want the BPM on screen because I;ve started to rely on them ideally it'd be cool not to have the BPM showed so I can still mix the tracks and not rely on the BPM being on screen and just cheating using that and matching the two numbers.

For the mean time i've put post it notes over them so I dont look but ideally wondered if it was possible to turn off in RekordBox

No, it's not possible and I seriously doubt it ever will be. Seems like the post its are the best option!