First of all I would hardly declare myself as a creature modeler, but since never saw anyone else doing this more or less obvious workflow publically I wondered how well it would work out. Pretty sure certain people with more ressources at their hand have already tested it.
At the end of this article is a small post mortem. I wished I would have 3 more days to completly refine this to a satisfying level, but sadly my time is currently very limited.

Rough sketches
Nothing to say about this, this is one of 5 sketches I made, to laying out the proportions / try different stuff.I wanted to do the detailing during the sculpting process from the beginning.

Base Structure
Based on the sketch I quickly slapped together the support structure wich is needed to build up the model

Sculpted mesh
I wish I would have made more images of the process itself, but I wanted to finish this as quickly as possible / not getting out of the flow

Scanned mesh
Result of the photogrammetry process. This was besides drying the model the most time intesive process

Edited mesh
This was created faster than I initially thought it would be. See post mortem for details

Final Render
Build a suit for this person, textured it in substance painter and quickly rigged it. Not satisfied with the end result at all: Eyelids would need additional sculpting, rigging and suit design is partly bad. And the gun model was quickly slapped together. But again I had only effectively one weekend to bring things together after the head was made. Background images is from a payed collection. Used substance painter for texturing

Post Mortem

The last time I've physically sculpted has been significant time ago, and it was actually only a short term training I've recived and as said I never got into creature sculpting that deeply (thats one of the reasons I choosed an alien model as subject)... also I had no experience with the material I'm using, so I was very conservative on the thickness side of things....
so sorry for the crappy model

First of all this techniques comes with its own limitations, most noteable:
Gravity, time and level of detail. Surprisingly building up the model itself is quite fast and is quite compareable to a full digitial modeling, but to get it dried and photoscanned, needs significant more time. On the plus side you get more often those "happy accident" situations, especially when creating the details and the model itself has a more organic look.

Sadly, due to ram restrictions I could not go to high detail in agisoft to capture all the fine details, wich would greatly help. As for the material I'm divided... a white material gives you a nice cavity / dirt map to work with additionally, but on the other hand it interferes with the lights captured during photogrammetry (spec highlights).

I used instant mesh for auto retopo, since I don't have the time to go full on manual retopo (and I don't wanted to rely on zBrush for this experiment).
As weapon of choice I used blender, wich does have some great and not so great features.

On the plus side editing the imported mesh was quite a breeze. Import obj, clear additional geometry, fill the holes with loop selection and fill face, tripple them, and add some additional geometry (especially in the neck part) via additive sculpting was a practically a no brainer without big hickups.
Also uv unwraping the mesh was a smooth ride, using loop + shortest path selection (create a shortcut for this). There was only one part wich refused to correctly unwrap due to some intersecting geometry wich needed a few minutes more to invest.

Not so smooth was the additional baking, wich created some seams if you use a lower densed mesh to bake to. (You need an additional subdivision modifier, wich again goes heavy on memory usage....definitive room for improvement in that area...
Basic rigging of the medium mesh was also quite good, only a few weight maps needed manual editing.

The rest of the model was quickly slapped together to show something nice to render.

In the end I would say its a feasible method for some close up models if time is not a problem. If you could do the scanning process without waiting the model to dry, and do the revision process during the sculpting session itself you could really use it in a real life production environment