Hi, I have the same problem on 5.4.3. Any updates on this topic?
Edit: I found that thread: Level Sequence played in reverse will crash built game, or cause assert in editor - #4 by Mobiius_D11
with same stacktrace.
bug: Unreal Engine Issues and Bug Tracker (UE-220346)
is fixed already and will be part of 5.4.4
Workaround before fix release - just destroy LevelSequencerActor and create new one just before set new sequence.