The sharpshooter feat only works with actual ranged weapons (like bows and crossbows), which is why you won't see any benefits when casting spells like eldritch blast. This is actually by design, because ranged weapon users need these specific advantages to keep up with spellcasters in terms of effectiveness. When you're making ranged weapon attacks, sharpshooter lets you ignore those pesky high ground penalties and even gives you the option to trade accuracy for extra damage (quite handy when you're confident about hitting).

Something interesting to consider - while spells don't benefit from sharpshooter, they have their own advantages like being able to target specific saves instead of AC, and they often come with additional effects that weapons can't match. If you're building a spell-focused character, you'll want to focus on boosting your spellcasting ability score instead (and keep an eye out for items that enhance spell damage, they can make a huge difference).

Just remember that even though your eldritch blast makes ranged attack rolls, it's still considered a spell attack, not a weapon attack. This distinction is important because quite a few game mechanics treat these two types of attacks differently.