Sure you can do that basically by adding Conditions to the transitions. Put all of the statuses for both workflows in a single workflow, then add Conditions to each transition to allow one or the other.
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You can't really create 2 workflows for the same issue type.
What you could do is create a hybrid workflow where you have all transitions set up but on those that should only be accessible for administrators you can add a condition based on the user being in a group/role
Your basic user would then have one flow and the administrators would be able to use the exceptions (shorter path, less mandatory fields,... )
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