The 'embryo' one should be doable. It's a nice render but not what i would call very complex in lighting or shading. A good HDR with some color variation + IBL + render as HDR + tweaking in photoshop should get you pretty close.

The other one is gonna be much harder as it's using misss_fastskin, and that shader has all kinds of features that are not really possible in firefly AFAIK. Stuff like driving the SSS with GI, SSS bleeding into shadows, bumps getting softened with SSS etc. If you want to give it a go then i'd start with getting the lighting of your scene to that level first, maybe render out multiple lighting setups and blend between them. Then start on the shading, with custom maps to control SSS, specular, bump, diffuse. Maybe an edge falloff pass so you can tweak the specular and reflection in photoshop. You'll also need to find high quality textures, with well made bump maps.

Huge amounts of work in any case.