Let’s answer with arguments, not emotions
When the government has armored vehicles, it’s OK.
When protesters have armored vehicles, it’s not OK.
For me, this is simple. It depends on the kind of opposition groups.
Groups worthy of support are those for democratic rights, including specific minority rights or minority rights in general.
Groups that are anti-democratic, racist, antisemitic, or anti-Zionistic should be outlawed and certainly not receive any support from anyone.
NB: Israel is a minority country facing not only genocide but also around-the-clock lie-based global attacks no different from ancient Jew bashing. A practical rule of thumb could be: Any group refusing to agree with the Working Definition of Antisemitism is anti-democratic and dishonest.
One complication to bear in mind is that left-wing and right-wing often are the opposite here. The IDF and secret service bosses and rich people in Israel vote left-wing. Some ethnic minorities are pro-Zionistic, while other ones are anti-Zionistic, as a group. (Every group has exceptions.)
One could/should still object: The Left might lack the money to fight city hall, so the international community should help them. This might be true for any country but not Israel. The number of NGOs to assist minorities is here larger than in any other country in the world. We’re all activists. Of the 10M citizens, some 10M are dissidents on one thing or the other. Also, our High Court is directly accessible to anyone and even sends anti-minority or undemocratic laws to the wastebasket. The plans of the current government to curb this power are being fought tooth and nail by hundreds of thousands of demonstrators and the opposition for 21 weeks now and counting. If the government really tables these bills, millions will take to the streets. We have five national organizations for the protection of the child. Our State too is run on capitalism, the banks keep our people poor, but we resist. We lack no people, organizers, or money on any issue. Our free press covers the whole political spectrum, even in English, dwarfing the US. We don’t need countries, activists, or the UN muddling in our politics either. The idea that we lack ethics is probably Antisemitic—the old bigotry that Jews are evil and cruel. Biden’s opposition to judicial overhaul in Israel indeed helps us, but we’d do very well without that too.
So, ignore the right-wing/right-wing dichotomy. Just ask about the group to receive foreign aid: Whom does it support, and whom does it hate?
One last complication is that liars put the word Truth on their programs, haters the word Love, and terrorists the word Democracy. So, it needs some serious investigation if they stand for what they claim to promote.