I am getting intrigued by this question that I don't have the sufficient knowledge to answer it, I've looked up when black holes collide "non-directly" but that doesn't really apply to my question nor if its possible to do this.

I know that slight deviations of their trajectories would cause them to spin on each other or slingshot them but what would happen if we accelerate them at near light speeds and collide them both directly to their centers of mass?

Since black holes are massive their inertias would be huge, where would all this inertia go?

Or would the black holes disintegrate each other under the extreme conditions (they shouldn't)?

Or something else?

For reference, these black holes are equally massive and aren't spinning rotationally.