⚡Parent & Child Transform

You can also preview and modify the interactive transforms of child and parent objects at a glance from the inspector. These are loaded into memory as needed, so it doesn't hurt performance.

The foldouts are closed by default, and the inspectors are only created when you open them. The entire procedure happens seamlessly, so it doesn't cause any delays or slowdowns.

Technically, as there are no limits, you can open the inspector of thousands of child objects at once. But, as expected, after a certain point, it will slow down.

Limitation

The size displayed in the main transform inspector is updated automatically to reflect the current state of the object. However, the sizes shown for parent and child objects are not updated in real-time. They are only calculated when you first open the foldout. For example, if a child object has a size of (1, 1, 1) when the inspector is first opened, and its size changes during gameplay, that change will not be reflected in the inspector unless you reselect the object.

You can use the refresh button to update it.