I am highly interested in who's working on Final Fantasy VII Remake so I took at look at all FFVII staff to see who's still working at Square Enix. For this I have not included anyone who has not been credited in a Square Enix title since Final Fantasy XIII or Kingdom Hearts Birth by Sleep since this is well over five years ago, majority of staff went on to work on Final Fantasy XIII-2 and Kingdom Hearts 3D respectively and staff are confirmed to have left the company after XIII. Additionally, hardly anyone was credited for working on XIV or Versus XIII in any capacity. I also noticed a very large amount of the staff left the company after VII or VIII. Some would stay on and work on titles like X, X-2, Dirge of Cerberus and early KH titles but as you can see almost everyone appears to have left the company or simply has taken up roles in other the company. Another thing to add, FFVII was of course made almost 20 years ago so it should come as no surprise so many staff are gone.
Tetsuya Nomura also confirmed he is the youngest person from the original FFVII to be working on the remake. However, I unfortunately cannot find the age for most of these staff.
Confirmed to be still at Square Enix
Motomu Toriyama - 90% chance he's working on VII Remake
Shintaro Takai - 70% chance he's working on VII Remake
Hiroki Chiba - Busy with World of Final Fantasy
Yusuke Naora - Busy with FFXV and younger than Nomura
Hiroyuki Ito - was too busy to work on the XIII saga with what appears to now be XVI so I find it highly unlikely he'd work with BD1 now.
Likely still at Square Enix
Jun Akiyama - Likely working with Ito, younger than Nomura anyway
Masaru Oka - KH3D writer, if still at SE almost certain to be working on KH3
Hideo Kubota - Last SE title was Lightning Returns
Takanari Tajima - last SE work appears to be Type-0 HD
Unlikely
Tetsu Tsukamoto - last SE work was XIII-2
Manabu Inokuchi - last SE work was The 3rd Birthday
Ryusuke Sasaki - last SE work was XIII-2
Takayuki Odachi - working on XV reportedly
Takayoshi Nakazato - working on XV reportedly
Takatsugu Nakazawa - working on XV reportedly
Yusuke Tanaka - last SE work was XIII-2, someone by same name working on Metal Gear Solid
Yoshiyuki Oku - conflicting reports, some say Lightning Returns last work at SE, someone by same name working on Pokemon games
Freelancers
Nojima - confirmed
Hamauzu - younger than Nomura
Uematsu - Would be surprised if he's not
Amano - Would be surprised if he's not
Tetsuya Nomura also confirmed he is the youngest person from the original FFVII to be working on the remake. However, I unfortunately cannot find the age for most of these staff.
Confirmed to be still at Square Enix
Motomu Toriyama - 90% chance he's working on VII Remake
Shintaro Takai - 70% chance he's working on VII Remake
Hiroki Chiba - Busy with World of Final Fantasy
Yusuke Naora - Busy with FFXV and younger than Nomura
Hiroyuki Ito - was too busy to work on the XIII saga with what appears to now be XVI so I find it highly unlikely he'd work with BD1 now.
Likely still at Square Enix
Jun Akiyama - Likely working with Ito, younger than Nomura anyway
Masaru Oka - KH3D writer, if still at SE almost certain to be working on KH3
Hideo Kubota - Last SE title was Lightning Returns
Takanari Tajima - last SE work appears to be Type-0 HD
Unlikely
Tetsu Tsukamoto - last SE work was XIII-2
Manabu Inokuchi - last SE work was The 3rd Birthday
Ryusuke Sasaki - last SE work was XIII-2
Takayuki Odachi - working on XV reportedly
Takayoshi Nakazato - working on XV reportedly
Takatsugu Nakazawa - working on XV reportedly
Yusuke Tanaka - last SE work was XIII-2, someone by same name working on Metal Gear Solid
Yoshiyuki Oku - conflicting reports, some say Lightning Returns last work at SE, someone by same name working on Pokemon games
Freelancers
Nojima - confirmed
Hamauzu - younger than Nomura
Uematsu - Would be surprised if he's not
Amano - Would be surprised if he's not