Just war is not sinful. The Eastern Crusades stopped the Muslim advance from that direction for several centuries. The Iberian Crusades eventually rolled back the Muslims.
The Inquisition was confined to investigating public, baptized Catholics plotting to overthrow church and state. Public Jews and Muslims were outside the scope of the Inquisition and it did not operate in places like France or Germany were there were Protestants. Only those Catholics who did not repent were burned at the stake. This treatment was far more humane than the ripping out of the intestines of those English, Scottish, and Irish Catholics who refused to apostatize.
The Iberian Crusades could not have succeeded without the Inquisition. Aside from abuses that inevitably occur in war, how was any of this sinful?
To kill someone because they don’t believe as you do is not murder? What do you call it, then?