I'm bad in creating instructions
A7Tool:
File > Load A7
Sections > Export all (will create a sections Folder with all partiton Headers and payloads)
RFS > Export Files (will create a rfs Folder in your Firmware Folder with all fs files)
Tools > Strings.bin Editor
strings.bin Editor
File > Open (select the strings.bin file which is located in the rfs Folder)
Now choose one language you want to edit (not the empty ones) and edit all entries from one column.
After translating the strings file use
Strings > Save
Then use
Build > Compile
You'll get 3 new files in your rfs Folder:
strings.dat strings.head stringscompiled.bin
you can Keep the first two untouched
delete strings.bin and rename stringscompiled.bin to strings.bin
Now back to A7Tool:
RFS > Build RFS
RFS > Include
Build > A7Firmware
after that you have a new file in your Firmware Directory called "a7compiled.bin". rename it to firmware.bin and put it on your sdcard and follow the on Screen instructions to "update"
Big disclaimer: I have not tested A7Tool strings.bin Editor with a real device because I dont own an A7 dashcam yet! This means that it is possible that your dashcam will be stuck on boot (some call it bricked) because it can't load a probably corrupted strings.bin file. If anything unexpected happens I am not responsible.
If you brick your device it may be possible to recover it using an application called DirectUSB. But I'm not sure if this works. Maybe you need a special cable for that.