Getting difference between two versions of Shapefile using QGIS?

Maybe Layers by Field QGIS Plugin could do what you need

Layers by Field QGIS Plugin

I assume a situation like below:

1. When we visited last week, there were only three (3) schools. (Layer school_layer_1)
2. However, we found five (5) schools this week. (Layer school_layer_2)

And we want to know which schools are newly built.

Then we can use a Virtual Layer to find out suspicious schools.

The SQL query is:

SELECT * FROM school_layer_2
WHERE id
IN (
    SELECT id FROM school_layer_2
    EXCEPT
    SELECT id FROM school_layer_1
   )

The produced Virtual Layer (green circles) is a point layer with the records of difference between school_layer_1 and school_layer_2.

There is a new tool which was added in QGIS 3.12 called "Detect dataset changes" that does exactly what you want. It accepts any geometry type including point. The tool

Compares two vector layers, and determines which features are unchanged, added or deleted between the two. It is designed for comparing two different versions of the same dataset.

Original point:

Modified point:

Changes happened:

Please refer to the help above for more detailed information.

Information in the changelog for QGIS 3.12: https://qgis.org/en/site/forusers/visualchangelog312/#feature-add-new-algorithm-detect-dataset-changes