When an Xtension is updated, the only way to refresh the actions within the workflows (as per the documentation) is to delete them, drag a new copy and reconfigure.
We get that this is needed for not breaking existing workflows, but what is sorely lacking is the ability to locate them first.
What would vastly help with this process is one or multiple of:
A. From the Xtensions section, find workflows (at least prod published or all with visible status) that utilize actions from this Xtension - to be able to know where to look for what needs to be updated.
B. From the action editing pane in the workflow designer, show the API/action version - to be able to know what is the version of that action (not all updates change all actions after all).
Sidenote - Assuming that built-in actions actually work similarly (as in - they don't update automatically), the "B" above would also help with troubleshooting of standard actions as well, as a person would be able to see that they are using an old version of the action and should refresh it.