Hello [mention removed],
Thanks for your report. I’ve reproduced this error in UE versions 5.4 through 5.6 including a source build from Main at CL (40574608).
I also confirmed that the crash does not occur in UE 5.3 due to the previous serialization method used.
I’ve escalated this regression to the internal engine team and created a JIRA report. The issue will soon be visible on the public Unreal issue tracker at:
Please note that Epic ultimately determines whether the issue will be made publicly accessible, and the process may take a few days. The tracking link might not work immediately.
As a temporary workaround, your proposed fix remains valid. I’ve included a link to your pull request in the bug description so the developers can review and consider it directly.
I’ll go ahead and close this case for now, but feel free to reply if you have anything else to add.
Best,
Francisco