In Jira, story points are implemented via a custom field called "Story Points".
You can sync Jira Story Points field as a simple text field.
Make sure that you have Story Points field on both sides.
Source Side
Add the code below into the Outgoing sync to send Story Points field data
Data Filter
replica.customFields."Story Points" = issue.customFields."Story Points"
Destination Side
Incoming sync
add synced Story Points field data
issue.customFields."Story Points".value = replica.customFields."Story Points".value