Hi Eyal,
Welcome to the community!
I’ve moved your post to a new thread since the thread you had posted in was over 2y old. Per the FAQ, please don’t resurrect posts older than 2 months.
Regarding your question, the reason we advise people to set multi-criteria properties via the UI is that it’s fiddly and hard to get right when done by hand.
For instance, for your example, you’re going to have to set two different items:
sonar.issue.ignore.multicriteria.e1.resourceKey=**/*.cpp
...
sonar.issue.ignore.multicriteria.e2.resourceKey=**/*.hpp
HTH,
Ann