I shoot an FNP-9 left handed. The magazine release is reversible (step by step instructions with pictures on the FN Forum) The FNP-45 has the magazine release on both sides, if you are interested in that caliber. There is no safety (DA/SA operation), and the decocker is ambi for all the FNP models.
Pistols that have less controls are easier for left handed operation. DA/SA operation (like the FNP) or Glock safe action, means no safety to fumble with (if the safety is set up for right handed shooters). Most pistols can chamber a round by pulling back on the slide and releasing it (instead of fumbling with a slide release set up for a right handed shooter). Pistols that are hard for me to use left handed have a safety and a magazine release set up for a right handed shooter. Pistols that are easy for me to use left handed have ambi (or no) safety, and ambi (or reversible) magazine release.
Try looking at FNP, Smith & Wesson M&P, Ruger SR9. I know a left handed shooter who swears by his Glock, but the magazine release on his Glock is hard for me to work.