If this is a one-off task, then one possible approach would be to use the JIRA Command Line Interface (CLI) add-on, which provides actions like createIssue and createOrUpdateIssue that can create an issue. Both accept parameters that specify the issue type and, in the case of a sub-task) the parent issue. The How to create projects or sets of issues based on a template article might be helpful in this regard.
If you want to always create these “template issues” whenever a certain condition is met, you could use the Create on Transition add-on as described in this How to Automatically Create a Standard Story When Creating an Epic recipe.
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