I think it’s not so much that the Accessport is “incompatible”, but that COBB just haven’t made MAF compatible files, nor have any of the US tuners who use the COBB system and Accesstuner as their baseline.
Mountune still uses a rebadged Accessport as the delivery device for their UK tunes. Mountune has clearly taken it and done their own software thing to get it to work for UK cars, and isn’t using COBB’s as a baseline
The map switching functionality we have is part of the base software written by COBB into Fiesta ST functionality, and made available to all the US tuners that use Accesstuner, not something each tuner came up with individually. The programming for it only been done once (by COBB’s team).
COBB is in an intermediate place the ECU tuning world in that regard, having made an whole tuning ecosystem available to third parties that’s halfway between factory style “ecu-reflash” and “standalone” ECU capability while retaining the factory ECU, instead of simple reflashes or full replacements. A few other companies have done similar things, but it’s not the “traditional” approach to ECU tuning that came out of the 90’s and 00’s. Specifically having made a system with “lockable” (to both pro-tuner and locked-to-vehicle) tune files to enable third party professional tuners to build a business around it. Most other companies that have gone with a similar approach have gone either with proprietary flashes, or “open” user-tunable flash files
The question is whether it’s actually worth it trying to compete with the established UK outfits like Pumaspeed/Mountune/MaxD that have been around a lot a whole lot longer supporting UK market “fast Fords” and have built up good reputations, and the whole issue of overseas support.