the new qgis plugin allows to change the datasource of layers already loaded preserving all properties and settings (symbology, labels, joins, relations) using methods already exposed. The plugin operates in two operating modes: per layer or per project. In the first way it is possible to operate directly on layer right clicking on legend items, modifying the datasource type and string and applying the edits.
in the second way clicking on toolbar icon, the plugin exposes on an editable table datasource types and connection strings for all the loaded layers allowing global edits with a find and replace function or a direct edit on the cells. Datasource are not modified directly; modified cells are marked in yellow and the edits have to be applied to be effective, and visible on map canvas. Valid edits are marked in green while the invalid ones in red.