Create issue with link via rest api

I want to create an issue with a link to an existing issue. I’ve read a lot about linking issues and I have read often, that the link has to be established after the ticket is created. My Problem is, that I dont want to make the link afterwards because the performance of my application would decrease.

Therefore, my question is, is it possible to create a issue with a “created by”-Link immediatlly ?

What I have already tried is:

from jira import JIRA
jira = JIRA(...)
field = {'project': 'SLIC', 'summary': 'New summary1', 'issuetype': {'name': 'Task'}, "update":{"issuelinks":[{ "add":{"type":{"name":"Created by", "inward":"is created by", "outward":"created"},  "outwardIssue":{ "key":"Test-15" }} }] }}

I am using Jira on Premise solution on a windows system.