Undertale Plus is a fan-made mod for Undertale that adds lots of settings, ranging from functional, aesthetic, quality-of-life, and many more! Examples include:

• 60 FPS and Widescreen support
• Visible Armor in the Overworld
• All Console-Exclusive Content
• Bug Fixes
• Colored Sprites and Battle Backgrounds
• Reimagined Soundtrack

All of which are optional, and can be toggled however you'd like!