Hi @sx3 I also have a Gria HS. I would say OH is actually much more flexible than HS - even though we have spent a lot of $$$$ on the HS ;-(
I find the HS quite difficult to do more than the basic stuff, and the tools really haven’t moved on a lot. With all the IoT and home automation stuff going on it really is getting left behind. That’s why I investigated OH - and I’ve not looked back. Once you get your KNX to talk ‘internet’ there won’t be any turning back 
I even have my Amazon Alexa switching my KNX lights on and off…
Take a look at the KNX binding and the support in this thread [SOLVED] KNX Binding: no confirmation reply received