OET interlinear JOS 18:12

uW Translation Notes:

Note 1 topic: figures-of-speech / explicit

QUOTE_NOT_FOUND: to the mouth of the north

(Some words not found in UHB: and=he/it_was to/for=them the,border on,side north,on from/more_than the,Jordan and=he/it_would_go_up the,boundary to/towards slope Yərīḩō/(Jericho) on,north and=he/it_would_go_up in/on/at/with,hill_country west,to and,coming_out ends_of,it wilderness,at house_of אָוֶן )

Here the word mouth has the sense of “end” or “edge,” perhaps because the mouth of an animal is typically at one end of it. Alternate translation: “on the northern end of their territory” or “on the northern edge of their territory”

Note 2 topic: figures-of-speech / personification

כֶּ֨תֶף יְרִיח֜וֹ מִ⁠צָּפ֗וֹן

slope Yərīḩō/(Jericho) on,north

The author is speaking of the mound on which Jericho was built as if it were a living thing that had a shoulder. If it would be helpful in your language, you could state the meaning plainly. Alternate translation: “to the northern slope of the Jericho mound”