Currently the "StringConcatenate" node is only available in the latest nightly version of ComfyUI. If you have problem try this version : link

Resources you need:

📂Files :

For base version
I2V Model : wan2.1_i2v_480p_14B_fp8_e4m3fn.safetensors or wan2.1_i2v_720p_14B_fp8_e4m3fn.safetensors
In models/diffusion_models
CLIP: umt5_xxl_fp8_e4m3fn_scaled.safetensors
in models/clip

For GGUF version
>24 gb Vram: Q8_0
16 gb Vram: Q5_K_M
<12 gb Vram: Q3_K_S
I2V Quant Model : wan2.1-i2v-14b-480p-QX.gguf or wan2.1-i2v-14b-720p-QX.gguf
In models/diffusion_models
Quant CLIP: umt5-xxl-encoder-QX.gguf
in models/clip

CLIP-VISION: clip_vision_h.safetensors
in models/clip_vision

VAE: wan_2.1_vae.safetensors
in models/vae

ANY upscale model:

• Realistic : RealESRGAN_x4plus.pth

• Anime : RealESRGAN_x4plus_anime_6B.pth

in models/upscale_models

📦Custom Nodes :

• ComfyUI-Custom-Scripts

• ComfyUI-GGUF

• ComfyUI-KJNodes

• ComfyUI-VideoHelperSuite

• ComfyUI-mxToolkit

• ComfyUI-HunyuanVideoMultiLora

• rgthree-comfy

• ComfyUI-Frame-Interpolation

• WAS Node Suite

• ComfyUI-Florence2

• ComfyUI-Upscaler-Tensorrt

• ComfyUI-MultiGPU