That’s a weird question, since a flavor of Leif’s work actually is an Omnia now.
That being said, presets that are supposed to emulate certain boxes only even partially work out if the original gear isn’t adjustable. Or else you’re trying to copy something that never has a bullzeye. 😉
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Why don’t you write down certain aspects of Omnia processing on air that you like (actual stations you can tune into and reference), and then try to match the preset & meta-settings with whatever best fits your processing goals. You could fail to sound like a specific station, even with the same box on the air. Keep that in mind.