Steps to reproduce:

Create a new Universal 2D project via Unity Hub
Edit > Project Settings > Editor > "Enter Play Mode Settings": enable Enter Play Mode Options and disable Domain Reload
In the Project Browser right click and Create > 2D > Sprites > Triangle and Select the texture
In the Inspector click "Open Sprite Editor" (or Window > 2D > Sprite Editor)
Draw a Cube Sprite container in the Sprite Editor
Do NOT click Apply in the Sprite Editor. Press Play to enter Play Mode
In the "Unapplied import settings" dialog that appears, click Apply
Observe the Console

Actual results: An exception is thrown:
Exception: AssetDatabase.ForceReserializeAssets cannot be used when in play mode
UnityEditor.AssetDatabase.ForceReserializeAssets (...)
UnityEditor.U2D.Sprites.SpriteEditorWindow.DoApply () (at .../com.unity.2d.sprite@6bfd14f568c2/Editor/SpriteEditor/SpriteEditorWindow.cs:1170)
UnityEditor.U2D.Sprites.SpriteEditorWindow.HandleApplyRevertDialog (...) (at SpriteEditorWindow.cs:865)
UnityEditor.U2D.Sprites.SpriteEditorWindow.RebuildCache () (at SpriteEditorWindow.cs:937)
UnityEditor.U2D.Sprites.SpriteEditorWindow.OnPlayModeStateChanged (...) (at SpriteEditorWindow.cs:838)

Expected results: Unapplied Sprite Editor changes are applied or reverted cleanly before the Play Mode transition, with no exception.

Reproducible with versions: 6000.0.0f1, 6000.0.79f1, 6000.3.20f1, 6000.5.4f1, 6000.6.0b3, 6000.7.0a2

Tested on (OS): Windows 11