Yes,
Provided you have your HALion content keys on the eLiscencer of the target system.
In short, most Stienberg Hosts come with some content libraries for HALion SE. You’ll need the dongle or soft-eLisencer with applicable keys installed on the target system to use that content in another DAW.
Example:
Dorico comes with several HALion libraries. If your Dorico key is on the system with your ‘other DAW’, then YES, HALion SE 3 can be loaded and use these sounds.
Example:
Cubase comes with several content libraries. If your Cubase key is on the system, then YES, SE3 should run happily in other DAWs, and be able to play the HALion sounds that came with Cubase.
Example:
You’ve purchased a HALion Library such as the Steinway Grand. If you have the key to Stienway Grand on the target system, and either a Steinberg Host that came with SE, OR, the ‘free HALion SE key’, then SE3 can play this from any host.
Example:
You have Dorico, but your Dorico key isn’t on the system (Dongle, or soft eLisencer).
In this case, another DAW can NOT load HALion SE unless you have the free SE key installed there.
The content libraries that came with your Stienberg host(s) will not show up or play, as those require your Dorico key to be unlocked.
Here are some other related threads on things “HALion”.