https://www.polygon.com/2018/7/16/17576824/game-design-accessibility-deaf-hard-of-hearing

Designing a game to be welcoming for players who are hard of hearing might not be as complicated as you think, but it does take a bit of education. Learning how to take the information that’s often provided exclusively through audio and present it through other means has its challenges.

The video above, from Game Maker’s Toolkit, does a good job of discussing some of these obstacles that might not be immediately apparent to most players or developers.