I would recommend you go with the device that's light like a MacBook or Air and do your heavy lifting in Azure or on a cheap NUC / commodity hardware. Build and test the VM out on your portable, then move them off when they need extra RAM / CPU / threads or several people will test against them.
It's possible to run Windows on bare metal but that's a hassle to hard partition your storage and if you choose wrong, it's a pain to fix the partitions. Virtual is so much better whether it's ESXi on a home lab or Fusion on top of macOS.
Visual Studio runs incredibly well in a small Azure VM for pennies a day and you only pay for it when you start it up. Deallocate the machine when you're not using it and it's essentially free.
I do the above with a 2015 MacBook / 1.1 GHz mobile CPU / 8 GB RAM.
- Negative wise - Fusion and Docker on the SSD perform just amazingly well for light work, but if you have 2 beefy VM that belong on 8 cores, you'll not be happy.
- Positive wise - MacBook 2015 and up runs 4K display amazingly well, charge over USB C with a suitable display. I'd have thought I'd need more horsepower 18 months ago, but Azure and home lab setup let me run the SQL/ASP.NET/IIS loads off the Mac and I just make the scripts / see the pixels locally. As long as I'm connected to power, I have no issues running it at full CPU.
- The new Air will thermally throttle less than my MacBook and the MacBook Pro will run substantially more CPU before thermally slowing (possibly three instances of Windows based on how much work you hammer them with). You won't harm it at 100% usage - just the Air and MacBook line don't dissipate heat and throttle the CPU sooner than the Pro or iMac. This Mac is a dream machine to me for how well it's been usable for hard core infrastructure and dev-ops tasks.
For the price of a beefy MacBook Pro I'll always go with an SSD iMac or Mac mini and the Air/MacBook (or even the iPad Pro now) - but that's my preference and I get why some people prefer to spend the $3k-$4k all on one machine. I want super fast and super small and to develop the install scripts then automate making them on virtual servers whether they're in the cloud / data center / or co-located in my office at home.