To find free animations that are predominantly in white color, you have several options:
Free Animation Libraries and Websites: Websites like LottieFiles, Mixkit, and Pixabay offer free animations, some of which may be available in white or can be customized to suit your needs. You can browse through their collections and use filters to find animations that match your criteria or have customizable color options.
Open Source Animation Tools: Use open-source tools such as Blender or Krita to create animations yourself. These tools allow you to design animations according to your specifications, including setting a white color theme.
Customizable Icons and Vector Graphics: Websites like Flaticon or VectorStock provide a variety of icons and vector-based animations. Oftentimes, these can be edited using software like Adobe Illustrator or Inkscape to adjust the color to white.
Animation Software with Color Customization: Animation software such as Adobe After Effects, even in its free trial version, may offer pre-made animation templates where you can customize the colors, layers, and keyframes to be predominantly white.
Online Communities and Forums: Platforms like Reddit, DeviantArt, or Behance allow you to connect with animators and designers who often share free resources or can guide you towards finding suitable animations. You can search these platforms for white-colored animations or request recommendations.
Educational Platforms: Courses on platforms like Coursera or Udemy sometimes provide free or affordable resources, including downloadable animations, which you can use or adapt. These platforms might also teach you how to alter states like color in an animation to match your needs.

Make sure to check the licensing terms of any animations you use to ensure they are truly free for your intended use.