Strip picker

__init__.py

import bpy
from bpy.props import StringProperty


class TEST_PT_layout_panel(bpy.types.Panel):
    bl_label = "VSE Strip Picker"
    bl_category = "Test Panel"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "scene"

    def draw(self, context):
        scene = context.scene
        layout = self.layout
        
        col = layout.column()
        col.prop_search(scene, "prop", scene.sequence_editor, "sequences", text="Pick Strip")
        if scene.prop in scene.sequence_editor.sequences:
            col.label(text=f"Selected: {scene.prop}")


def register():
    bpy.types.Scene.prop = StringProperty(name="Selected Strip")
    bpy.utils.register_class(TEST_PT_layout_panel)


def unregister():
    bpy.utils.unregister_class(TEST_PT_layout_panel)
    del bpy.types.Scene.prop
    
if __name__ == "__main__":
    register()