As the following article suggests the XF9000 soundbar has got the E-ARC update "Sony told us that recently pushed firmware updates are carrying eARC feature capability to its 2018 Master Series TVs (all A9F and Z9F models); AV receivers including the DH780, DN1080, ZA810, ZA1100, ZA2100, and ZA3100; and sound bars including the HT-ST5000, HT-ZF9 and the HT-XF9000"
https://hdguru.com/firmware-updates-for-earc-begin-to-arrive/

If the matching soundbar for the set already has E-arc I find it bizarre that the TV itself has not got it yet

Does anyone have any info on when this will be?
As the XF90 has been included in the 2019 range they don't really have an excuse for not adding this critical future audio output
Heck why they haven't done it will all capable sets from the past year I do not know as it is only a matter of a firmware upgrade