Exiftool command to embed the data
exiftool -GPSCoordinates=40.6892,-74.0445,10 -GPSCoordinates-fra-FR=10.6892,-14.0445,10 Y:\!temp\Test1.mp4

Exiftool results using the -v4 option

  | | | ItemList (SubDirectory) -->
  | | | - Tag 'ilst' (98 bytes):
  | | |     16b8: 00 00 00 31 a9 78 79 7a 00 00 00 29 64 61 74 61 [...1.xyz...)data]
  | | |     16c8: 00 00 00 01 00 00 00 00 2b 34 30 2e 36 38 39 32 [........+40.6892]
  | | |     16d8: 2d 30 37 34 2e 30 34 34 35 2b 31 30 2e 30 30 30 [-074.0445+10.000]
  | | |     16e8: 2f 00 00 00 31 a9 78 79 7a 00 00 00 29 64 61 74 [/...1.xyz...)dat]
  | | |     16f8: 61 00 00 00 01 46 52 1a 41 2b 31 30 2e 36 38 39 [a....FR.A+10.689]
  | | |     1708: 32 2d 30 31 34 2e 30 34 34 35 2b 31 30 2e 30 30 [2-014.0445+10.00]
  | | |     1718: 30 2f                                           [0/]
  | | | + [ItemList directory]
  | | | | GPSCoordinates = +40.6892-074.0445+10.000/
  | | | | - Tag '\xa9xyz', Type='data', Flags=0x1 (UTF-8), Lang=0x0000 (25 bytes):
  | | | |     16d0: 2b 34 30 2e 36 38 39 32 2d 30 37 34 2e 30 34 34 [+40.6892-074.044]
  | | | |     16e0: 35 2b 31 30 2e 30 30 30 2f                      [5+10.000/]
  | | | | GPSCoordinates-fra-FR = +10.6892-014.0445+10.000/
  | | | | - Tag '\xa9xyz', Type='data', Flags=0x1 (UTF-8), Lang=0x1a41 (25 bytes):
  | | | |     1701: 2b 31 30 2e 36 38 39 32 2d 30 31 34 2e 30 34 34 [+10.6892-014.044]
  | | | |     1711: 35 2b 31 30 2e 30 30 30 2f                      [5+10.000/]