I looked at HRV at the start of my build but here in the UK they are mega expensive, £300+ for a basic one so opted for a normal Manrose (6") kitchen extractor fan, pulls 230 m/hr.
I did it because it was getting stuffy sometimes in there but i then found that when ive got machine and inline extractors running it was pulling in fresh air through the wall extractor, so i just changed the whole fan in reverse and in the winter it has has a flap cover to stop feezing air coming in, and my heating going out, likeni say to the missus when she stands st the front door wide open in the winter “were not paying to heat the street” 
in all it was about £50 and it all happend by accident 
Here in Louisiana, I wouldn’t want an HRV (Heat Recovery Ventilator) as the very high humidity would be an issue. I would want to go with an ERV (Energy Recovery Ventilator), as an ERV doesn’t just act as a heat exchanger, but it also is designed to moderate the humidity gradient, i.e. keeping more of the outdoor humidity outdoors.
I haven’t jumped on it, however, as I’m not sure how an ERV would handle “contaminated” exhaust air from my various machines (CNC router, diode lasers, CO2 laser, fiber laser, et cetera). I haven’t found any data about whether components in the exhaust air stream would foul the “engineered resin” core of a typical ERV.
I’m currently content enough with my machines’ exhausts being plumbed through the wall above the open-joist “ceiling” at the rear/laser end of my shop, with outside replacement air coming in 30’/9m away on the other end of the building through a pair of automatic-damper inlets. That’s done a great job keeping exhaust air out of the shop, and I have a dehumidifier keeping the humidity down. I also have a nice mini-split heat pump keeping the temperatures within an acceptable range when I’m away (and plenty comfy when I’m present).
Of course, if this is also going to be a bit of a show-off-your-shop thread, um… I’ve got to get things a bit more photogenic before I snap inside photos, but I do have a slightly dated outside photo, at least, although it doesn’t have the air intakes…
(The shop couldn’t be more than 12’ wide due to the house, a natural gas line, and the required setback from the property line, so it’s 12’ wide. It couldn’t be more than 30’ long due to the driveway, house entry door, and a giant pecan tree at the other end, so it’s 30’ long. Building code here has tables for wood studs up to 10’ tall, but above that requires a structural engineer sign off, so it’s got 10’ ceilings. And the rafter hangers I used (to make it stronger against hurricanes and much easier to build solo, as I did) allowed up to a 30° pitch to the rafters, so it’s got a 30° pitch roof for maximum storage above the open-joist “ceiling”. Don’t even get me started on “1-hour fire-rated wall assemblies”, or you’ll be here quite a while. 
Oh, and I brought 100-amp service through to the subpanel in the shop, so if my next vehicle’s electric, I’m ready.)
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An air-to-air heat exchanger would be an asset if you can find one.
Undoubtedly! 
I was thinking more in affordable and compact options.
The air to air heat exchanger offers resistance to air passage.
So to get around this issue, the number of exchange channels is increased to reduce the resistance (drag) to passage but the dimensions are increased.
Another way is to use more powerful fan, but they are also noisier and more power consumption.
If you live very close to a river, a water-air heat exchanger (a “big” radiator) will do the work too. Eventually, a water pump is not even necessary if there is a sufficient difference in level.
The difference in level causes the water to circulate by gravity and the air is circulated through any extractor that is in operation.
Then there is still the combination of the two (ATU Air Treatment Unit). In which the water-air exchanger is mounted at the air inlet of the location to be acclimatized.
But in this case @misken had to sell the shed and all its contents to acquire the air exchanger. 
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