Create floorplan KML file in QGIS?

I import a building floor plan from DXF format to QGIS. When I export it to KML format and then import it in Google Earth, how can I put the floor plan to my desire building location? MY CRS is WSG84 already but I don't know how to specify the floor plan location (lat/long) in QGIS.

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I try to use the qgsAffine plugin to do the transformation. But no idea its usage. Anyone can post an example. Many thanks!!

Here is my coordinates:

Original x 0.3704 (EPSG:4326) to Target long 114.2031

Original y 0.52804 (EPSG:4326) to Target lat 22.3249