Is there any college that will give letter grades for transferred study.com courses?

[innen_oda]

Why can't a standard for all credits be created so there is no more confusion.

Because there's no financial/business incentive to do so, and government-initiated action is an anathema to the American way.

In all seriousness, the current status quo benefits individual universities, as it allows them to retain most of the power and decision-making. The only way this would change is if universities unanimously agreed to relinquish that control to an external body, which I can't see happening.