The product page in the shop says for Ampire: "Compatible with VST3, AudioUnit and AAX compatible host applications". If Studio One 3 can handle the mentioned formats as plug-ins (don't remember anymore), I would not know any reason why Ampire should not work. The new Ampire will NOT replace the old Ampire and is NOT part of Studio One versions earlier than 4.6.
Read more about the changes in the press release:
Hope this helps.
Have you checked the forums if there is some information? You can also ask your question there.
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