Something went wrong with celestial empires being not able to establish tributaries starting from A8 release, probably due to the religions update but no fixing from changing religions with cheat commands, probably to do with MoH itself because when countries were previously eligible for establishing tributaries they become unable to do so upon acquiring MoH. This is a major problem for the game because 1. since enforce tribute CB is still valid for countries in the MoH periphery the Chinese emperor keeps declaring wars on them without "establish tributary" wargoal; 2. for middle eastern countries benefiting from silk road for delicacies a China devastated by rebellions triggered by low mandate makes it hard for the middle east to urbanise; 3. for Europe a China hated by all its neighbours and battered by internal strife is not an interesting trade partner/expansion target, and Europeans are also effected by a shortage in delicacies supply. (Also frankly, Rome has way too few commerce reforms, a reform level the same as the Mongolians should surely not apply to a state which relies on trade and where formal contracts between merchants are already a practice.)