The Chinese company is said to have trademarked the name - OnePlus Tag - which suggests a tracking device is being worked on, or is at least a consideration for the future. Of course OnePlus Tag could mean something entirely different but given its competitor's offerings, it's probably safe to assume it's an item tracker.
The trademark - first spotted by DroidMaze and Neowin (via 91 Mobiles) - was filed on 18 May 2021 through Beijing Intangible Technology. No further details were provided within the trademark so there's no word on a release date or what features the device would offer.
We would expect it to use ultra wideband technology though, and it's likely you would be able to attach one to your keys or wallet in some way, allowing you to then use your phone to locate them if you lost them.
OnePlus will be a little late to the item tracking party if the OnePlus Tag does appear. Tile dominated this sector for a number of years, until it was met with some competition from Samsung with its SmartTag in January 2021 and then Apple in March 2021 with the launch of the AirTags.
OnePlus could undercut the other options available in terms of price though, whilst still offering good specs, as it does with its smartphones. For now, we will have to wait and see, but we will be keeping our eyes peeled for any future rumours surrounding a OnePlus Tag.