I checked the wiki thoroughly, and I don't find any specific trade rumor from July 6 about the Chiefs acquiring a wide receiver or tight end. The latest Chiefs-related news in the wiki covers injury updates (Mahomes, June 28) and the Chris Jones/Tyreek Hill reunion chatter from February, but nothing dated July 6 about a trade for a pass-catcher.
It's possible that rumor came from a source outside the wiki's coverage. If you remember where you saw it (a specific site or reporter), I can try digging deeper or check if it's from a different angle.