nprofile1qy2hwumn8ghj7un9d3shjtnyd968gmewwp6kyqpqfu7z83nd4jh5jz5hdwg25qyawc7swtzyq609lkz9q0m4rxwrytpq6pd3qt (nprofile…d3qt) Omnidirectional handhelds (non-HF) aren't going to broach a mountain range without a repeater, especially if you're both in a valley.
I think this ultimately comes down to what repeaters you can use. Hopefully there is a repeater on a mountain somewhere you both have line of sight to.
You'll have to search repeaterbook or w/e. You may luck out with a conveniently placed LoRA: https://meshmap.net/ https://meshcore.io/map
If voice is required, look for DMR repeaters.