Summary

Currently, neither the bulk operation screen includes Linked issues as an option nor the issue view has an option to bulk update/remove linked issues.

In some cases, that might require a lot of manual work due to a high number of linked issues.

Suggestion

Offer a way to bulk update/remove linked issues.

Workaround:

Create an automation rule:
1. Trigger:
Chose any type of trigger depending on your use case. If you only want to do it once, you may want to choose Scheduled trigger then run the rule manually.
2. Add Component > New Branch > Branch rule/related issues > Type of related issues > JQL:
Specify the JQL query returning the issues you need to edit.
Ensure there are no order by clauses and the issue you'll need to link to is not included in the query.
To include a list of issues, the JQL can be:
key in (key-1, key-2, key-3 etc)
3. Add Component > Action > Link Issues:
4. Publish and Run Rule.
5. Delete the rule if the issues were linked successfully.