Despite dominating the global smartphone AP market, MediaTek is yet to meaningfully break ground in the United States. While you can buy a few Dimensity-powered mid-rangers such as the Motorola Edge 2023, its high-end offerings often never make it to the region. A MediaTek analyst confirmed that could change soon (via @nirave on X, 9to5Google).
A "premium segment smartphone" powered by a MediaTek SoC will launch in the US later in the year. Unfortunately, there's no word about which OEM it will be from. Oppo, Vivo, Xiaomi, Redmi and other BBK affiliates (Realme, iQOO, etc.) are unlikely candidates as they have no official presence in region, although you can import their smartphones form abroad. That leaves us with OnePlus, Nokia/HMD Global and Motorola, because they're the only OEMs that launch high-end smartphones in the market.
Plus, there's no word about which high-end Dimensity SoC will make its US debut. The Dimensity 9300+ is out of question, as it will only power a handful of phones from Vivo and Redmi. That leaves us with the Dimensity 9300 and the upcoming Dimensity 9400. The former is one generation old and it might not make the cut, leaving us with the Arm Cortex-X5-powered Dimensity 9400 as the most likely option.