removing regional sports fee

You can’t you can only downgrade to a package that doesn’t include it. All carriers have the fee where as AT&T just chose to list it separately unlike others carriers just hide it in the package price 

The fee cannot simply be deleted. Packages Choice and above have the Regional Sport Networks (RSN) for the professional teams for where you live.

The only way the fee can be removed would be reducing the package to Family, Select, or Entertainment. If still available there is also Preferred Xtra, but total cost would be similar to Choice with the RSN fee. That is more bang for your buck if you don't watch sports, but is not the trimming of costs you are looking for.

So to trim costs you would need to lower your package. Only go to Entertainment if you watch ESPN, ESPN2, Pursuit, or FS1. Otherwise Select would be the better option.