[mantas]

In a democracy, any configuration can be changed given a qualified majority. If there's such configuration that it can't be changed by a qualified majority, then it's not a democracy.

Indirect democratic republic sounds painfully similar to people's democratic republics. Or infamous Putin's "controlled democracy" in Russia.

How would limited indirect democracy differ from autocracy such as in Russia or Belarus?

[IncRnd]

It seems that you aren't aware that The United States is such a Republic, properly called a Constitutional Republic.

[mantas]

I'm not from US so naturally don't know every single bit about US...

My country is a constitutional republic too. But here any article in constitution can be changed with a constitutional majority. Yes, it's not a simple 50%+1 majority democracy, but it's still a democracy where the population can implement whatever changes they wish. Given that large enough part of population signs off on it.