Downgrading 2020 13" MacBook Pro to run macOS Mojave

Can I downgrade the 2020 13" MacBook Pro to run macOS Mojave? This is the Model Id=MacBookPro16,2 - with Quad-Core Intel Core i7 of 2.3 GHz; sold in Europe in July 2020, that comes with Catalina pre-installed.

Unfortunately, many of my legacy software (in 32-bit) cannot be made to run under 64-bit. Some of my hardware relies on 32-bit software.

Are there hardware components in the 2020 models, which are NOT supported in previous? If one can downgrade, would that work with a time-machine backup? or would one need a complete re-install after erasing and re-formatting the disks, from a Mojave.ova file?

No, you cannot downgrade the model of MacBook that you have to run macOS Mojave. The oldest supported version of macOS for your model of MacBoo is macOS Catalina 10.15.4.

The general rule with macOS releases is that a machine cannot run a release older than the release that is current at the time the machine is first released. For example, your machine was released when Catalina (10.15) was the current macOS release - it won't run on an older macOS release.

That said, some have had varying levels of success running older, unsupported releases. There are a detailed set of instructions in this answer from /u/Wowfunhappy. You may have luck doing something similar but you will almost certainly have some technical challenges.

A far simpler approach is to install an older macOS release (eg, Mojave) in a virtual machine and use that to run your 32-bit applications. It certainly is possible with Parallels and may be possible with VMware Fusion and VirtualBox.

There is a startup check that prevents users from booting any version of macOS older than what was current at the time the machine was first released. As it so happens, just yesterday I wrote up a long answer on how to bypass this check: https://apple.stackexchange.com/a/402727/4027.

I encourage you to give it a read, but in short, you need to create a bootable installer, and add your computer's model and board ID to a file called "PlatformSupport.plist". This will allow your computer to try to boot the old OS, and either succeed or fail on its own merits.

So the question is, will Mojave actually function on your MacBook Pro?

The 2020 13" Macbook Pros come with two types of processors. The lower-end models with fewer thunderbolt ports have 8th-gen Intel Processors, whereas the higher-end models with more ports have 10th-gen Intel Processors.

Mojave does run on other Macs with 8th-gen processors, so I think there's a good chance that this first group of MacBook Pros could run Mojave. On paper, the hardware is compatible, and someone ought to try it!

Unfortunately, from what I can tell, I believe you have one of the higher-end models with a 10th-gen processor. I wouldn't expect that to work unless you can find a custom kernel—and even then I'd expect other hardware issues, similar to what I encountered.