Diffusers currently supports the following quantization methods.
- [BitsandBytes](./bitsandbytes)
- [TorchAO](./torchao)
- [GGUF](./gguf)  
[This resource](https://huggingface.co/docs/transformers/main/en/quantization/overview#when-to-use-what) provides a good overview of the pros and cons of different quantization techniques.