As mentioned in the MR IPv6 beta discussion, this is not currently expected to be part of the MR28 release due in a few months so would be in the second half of 2021 at the earliest I'd think.
The mention in the datasheet for OWE is that, for the WiFi6 AP models in question, it will "be enabled via future firmware updates"
I.e. the hardware has the capability, but it is not available currently.
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