thanks for the advice. the reason why i wanted to mix them is that i already have Sineoji and it works well. But i wanted to add a homeplug based AP to cover a wifi blind spot. Unfortunately Sineoji does not have such product so the choices are to mix brand or replace existing homeplug which is costly.
TP Link is AV2 1200 and Sineoji is AV2 1800, are they considered as same class? if they are indeed incompatible to work as 1 network, i hope i can form 2 separate networks with these homeplugs but again i'm worried they cause interference with each other and rendered one of them redundant. not sure i should proceed with this.