Is it possible for LTM4622 to generate negative output? Just like the one described in LTM8025 or LTM8065 datasheets (attached)?
Yes, the LTM4622 can also be used for negative output (inverting buck-boost) configuration. This is a dual part so both outputs will be negative (or you can float the other output if not needed). You can also refer to the LTM4625 demo board DC2721A-B for inverting configuration reference.