The Beretta 92FS is used in Perfect Order as Akihiko Tojo as his primary sidearm until he's told to change to the SIG SP 2022, first seen in Perfect Order's OP sequence, "UNDER/SHAFT".
The Browning Hi-Power is used by Jonathan "Jonah" Mar in Perfect Order as his primary sidearm until he's told to change to the SIG SP 2022, first seen in Perfect Order's ED sequence, "Ambivalentidea".
The Heckler & Koch Mark 23 is used by Lehmbrick as his primary sidearm until he's told to change to the SIG SP 2022, first seen in Perfect Order's OP sequence, "UNDER/SHAFT".
Hex uses an FN SCAR-L as her primary assault rifle in the Czech Republic. Note that she uses Magpul PMAGs which would work poorly in the rifle until later Gen M3 PMAGs.
The Magpul Masada is used by Koko's HCLI team in an attempt to give them common small arms. It's also seen in Perfect Order's OP sequence, "UNDER/SHAFT" and in the ED sequence, "Ambivalentidea". They're usually seen with EOTech sights attached to the upper receiver.