How to add gps data to a video

Hi everyone,

I've some H.264 video that has no GPS data, but I'd like add them in post-production during the encoding. In the Media Encoder metadata window there are GPS fields but I'm not able to edit them as you can see in the image:

Do you know any tricks to achieve my goal ?

I'm working on Adobe Media Encoder 24.11 (build 2) but I've the same problem in Adobe Premiere....

Thank you all in advance.

Simone