Either use the Manager and it's install from git -feature, or clone this repo to custom_nodes and run:
pip install -r requirements.txt
or if you use portable (run this in ComfyUI_windows_portable -folder):
python_embeded\python.exe -m pip install -r ComfyUI\custom_nodes\ComfyUI-Lavi-Bridge-Wrapper\requirements.txt
The following is autodownloaded:
https://huggingface.co/Kijai/t5-large-encoder-only-bf16/ to ComfyUI/models/t5_model/
https://huggingface.co/shihaozhao/LaVi-Bridge/ to ComfyUI/models/lavibridge
I couldn't get anything useful out of the llama2 version, it's included as separate node. Maybe I made mistake, maybe it just isn't that good, I don't know currently.