Lifting 2D Stylizers to 3D: Plug-and-Play Style Transfer for Gaussian Splatting

We present StyleLift3D, a plug-and-play feed-forward framework for transferring expressive 2D stylization to existing 3D Gaussian Splatting scenes. Existing methods typically require per-scene optimization or reconstruct a new stylized representation, while independently stylized multi-view images provide inconsistent supervision across viewpoints. StyleLift3D instead lifts such 2D style cues directly into a coherent 3D representation in a single forward pass. Our framework combines three components: Geometry-Aligned Style Lifting aligns multi-view style features with the content scene; Octree-Local Style Fusion establishes fine-grained style-content correspondence through scalable local cross-attention; and Structure-Preserving Gaussian Decoding predicts residual appearance and bounded geometry updates, with optional dynamic splitting for additional capacity. By performing style fusion directly in 3D, StyleLift3D preserves scene structure while maintaining consistent stylization across novel viewpoints. Experiments on diverse scenes, styles, and 2D stylizers demonstrate improved content fidelity, favorable overall user-study preference, efficient single-forward lifting, and plug-and-play compatibility with multiple 2D stylizers, compared with the evaluated optimization-based and feed-forward baselines.