Hybrid (5e Feat)
From D&D Wiki
You can take an additional subrace and add it to your list of racial features. This subrace could be from your race or a different one. For example, if you are a Wood Elf, you could add High Elf or Dark Elf to your racial features, or you could add Mountain Dwarf features.
By taking this feat, you become a mixed breed (or hybrid) and will start to show physicalities similar to the subrace. How these physicalities show is ultimately up to you and your DM.