How to connect 2 hot wire to a 2 pole MCB?

The output of an MCB is indicated by voltmeter testing. I'm serious. That's what Code says, you're not allowed to guess at voltages, you must measure. Because a MCB goes into a panelboard aka loadcenter aka service panel, and the voltage depends on how it is wired.

I'm planning to install a 2-pole Square D QO panel next week where one pole will be neutral because of a peculiar requirement.

Europeans in North America, or anything having to do with the Philippines, is likely to have this issue as well, and it will vary depending on where you are in the Philippines. That is one place you cannot make assumptions.