Hi,
On the 2nd row you have Image addon.
Maybe better would be to set image as background on the left column, then you have more design options to choose from.
OR
Use Image content addon
OR
yes, you can use Custom CSS for every object, just use unqiue Section/Row ID Name and class name
#RowName .sppb-addon-single-image-container
#RowName .sppb-addon-single-image-container img {object-fit: cover;}
If that may help you. Yes, I asked our developer to add "object-fit" as new option in upcoming updates.