Is it possible to set a bloom pass on materials that are inside/ other side of glass?
Bloom is implemented as a screen-space pass – it affects all pixels regardless of their source object/materials, assuming the pixels are over the chosen luminance threshold. So in terms of how bloom works, what you’re describing is fine.
Where I could imagine you might run into trouble would depend on the particular implementation of “glass”. For example if that glass uses a uint8 render target that clamps [0,1], then you won’t have much numerical range to work with for the bloom effect, as the RGB values have been clipped.
One way to render glass is MeshPhysicalMaterial’s “transmission” property, which should use a float or half-float render target when available and won’t clip your RGB values [0,1], so I would consider starting there.