I had my outer glow set up in the compositing for cycles, but it took way too long so I switched to evee. Im trying to create a golden outer glow for my character. I added another material and I tried to use the Material offset in the solidify modifier but since my object has transparency it creates the glow around the whole object not just my character. The object has a color image node and a alpha image node to make this character.
Solidify modifier is extruding geometry not textures.
If you need to generate thickness based on alpha you can fake it by using Volumetric shader (...but I'm not sure Eevee can handle it, so Cycles way).
In general ... If you think you can manage this effect with just Solidify ... you can use this Shader setup ...
The key to isolate specific material to be get into account (and only this material) by Bloom here is Bloom > Threshold.
To isolate material for bloom set shader Emission > Strength to something higher than anything in your Scene. Like here I set Strength to 10 and under adjust Render Properties > Bloom > Threshold until just a your "rim" is glowing.