Offline load .gpx file to my Garmin Instinct

these days technology ;-)

garmin connect app needs cloud

It's shame if you can't load this little simple .gpx file through Bluetooth...

I did not try, but when you connect instinct to PC using USB charge cable then you should be able to see it as mass storage. {I have seen that there is configuration about that in doc } But if you are outdoor then it is not solution :-(

Some smartphones are able to recognize usb devices but you need OTG cable.

www.tomsguide.com/.../connect-usb-drive-to-android,news-21213.html

Look into the Explore app, by having an Instinct you have rights to use this app too. It can transfer tracks/courses to watch w/o internet, but the tracks have to already be loaded into the app ahead of time.

I am using it too, but guys the case scenario is: "alone, high in the mountain, offline, no Internet, no WiFi, no 3G/4G, no cellular network, only phone with Orux/Locus with loaded offline maps where I can draw .gpx tracks on the go. 

We don't have ConnectIQ so we can't use this app for Fenix series: gimporter - Import FIT/GPX from Android Device https://apps.garmin.com/en-US/apps/de11adc4-fdbb-40b5-86ac-7f93b47ea5bb

Explore app can push track to the watch when you are offline, but can't load/open .gpx file, that's no sense for me...

Hello,
I haven't tried with Instinct. As soon as I get home, I'll do it.
But, I have already connected my Garmin Etrex 35T GPS to my Samsung Galaxy S8 smartphone without any problem via a USB/SUB-C adapter (provided by SAmsung) and the cable of my Etrex.
Via an Android file manager, I copied/pasted the GPXs from the smartphone to the GPS.

In the Explore app you can have free Garmin supplied offline maps, draw a track, and then transfer to the watch for Navigating a Course. I appreciate that Orux app allows user provided map files and so the Garmin provided maps may not meet your needs.

Ok, I managed to contact my Garmin Instinct to my pocophone by USB-c to USB Otg adapter. Find the Courses folder and paste a .gpx file, but all other files are .fit. Do I need to convert the gpx and how I can do this on my phone because I can find the new file in the watch through the navigation settings?

You are almost there! You don't put it into the Courses folder. You put your files into the NEWFILES folder. The watch will then process/convert the file(s) and put them into the Courses directory. You should then be able to see them in the Courses menu on the watch, remember they will have the track name not the file name.