Customize gpx navigation instruction wpt names

Hi,

i asked this question in the forum, but seems to be asked here. https://forum.locusmap.eu/index.php?topic=9438.0

I am preparing routes, using Locus to export them through gpx files to be imported in my sport watch.
Navigation instructions names seems to follow the app/system language, and in my own language (french) some instructions are too long and i would like to customize them.
example : a "left_sharp" instruction is, in french, "Tournez complètement à gauche" (it doesn't fit on my watch screen 🤣 )

I would need/want to change the gpx export instruction waypoint names <wpt>
See two trials, one made with my phone in english (UK) and wp name are in english, like on Locus route preview, and one in french (FR), same, like in Locus.

It seems not to be linked to tts file. I tried adding a fr.tts file, and can customize vocal announcement in Locus, but gpx export is still untouched.

Is it customizable somewhere else ? in router data (using internal lorouter (mainly offline)) ? Or is it hardcoded (which would be quite strange) ?

Thanks in advance Locus experts