Maybe you want to change your target CRS to EPSG:4326 because your target coordinates are given in latitudes and longitudes, not as web Mercator coordinates (EPSG:3857) which you are currently using in your "Transformation Settings" window.

Maybe you want to change your target CRS to EPSG:4326 because your target coordinates are given in latitudes and longitudes, not as web Mercator coordinates (EPSG:3857) which you are currently using in your "Transformation Settings" window.

As a dummy illustration, this is a PostGIS equivalent of what you are currently doing:

Whereas you want this:

The difference lies in the CRS of the input point. In the first case, it is set to EPSG:3857 and the result on a WGS84 (EPSG:4326) map is in the Gulf of Guinea. But in the second case, the CRS of the input point is EPSG:4326, and well, this is useless, but I kept the reprojection step, it's displayed where it must lie, in central America.