Sounds like you are trying to figure out how to clean the vent gasses before they enter the turbo.
Alot of what my plumbing does is vent the block somewhere other than the valve cover.
The old 1.5s had such a small oil return hole that when it got worn
so much gasses were trying to make it out that hole while oil was trying to drain back.
Eventually the vent gasses would carry so much oil with them that the engine would run away.
The factory cure was to run another hose from the front of the block
where the vacuum pump vents to
to the intake.
I think they did this to the 1.9 AAZ too.
So I made up something to do the same on my 1.6s.
And hooked it to the 3rd port on the 2.0 ABA puck.
Would be nice to have a catch can that drains the oil back into the port on the front of the block.
Crankcase vapors/oil mist don't hurt the turbo or intercooler.
Maybe not relevant here but
On the mk4 ALH, some say the intercooler works just like a catch can.
Apparently, it's not uncommon for turbo diesel intercoolers to collect oil like that.
As recommended I drilled a small hole in the bottom of it and, sure enough, a couple oz of oil drained out.
I plug it with a gasketed sheet metal screw and drain it periodically now.
There is a vent in the "front" of the block, left of the oil filter.
I prefer not to have oil deposits in the intercooler, or coating the turbine.
So I think I'll run the block vent up to the puck on the valve cover and the outlet of the puck to the catch can. Then maybe, if its even an option, I'll run the catch can vent to the intake ahead of the turbo.
With the possibility of condensate collecting in the catch can I'll probably have to put it on the oil change schedule for dumping.
The trick is finding a place to mount the Moroso catch can....
Is not there blowby pressure in the crankcase? Would gravity be enough to push the oil down or would the pressure push it up.
I have put long lines made from tubing from the valve cover out the back of cars back in the 60's. The long line helps to keep dirt out of the motor. Have seen filters to keep dirt out.
https://images.app.goo.gl/JZK4NwUHBewUoyGL8
Looking at this solution.
I prefer not to have oil deposits in the intercooler, or coating the turbine.
I think you said that earlier. I just thought I would mention that those oil deposits don't hurt either one any. Doing extra work for a non-problem doesn't make sense to me. It's a lot like refusing to eat because your peas are touching your potatoes. Also, venting unburned crankcase vapors to the atmosphere can both make a mess and is certainly environmentally irresponsible.
I'm routed to the Moroso catch can now.
It has a breather filter as well, so solid pollutants going into the atmosphere are highly unlikely.
There's a lot going on under the Samurai hood with EPS, remote oil filter, intercooler and now a catch can...
When I go to a snorkel air intake routing the catch can vent to the intake could possibly happen.