It's not so much the board, but getting the bios to recognise the cpu. There's only so much room in a bios chip, and with the amount of info with 1st and second gen, all the ram stuff etc, then you try updating fixes, any new info, instructions for changes and fixes etc, it's too much. So it's got to be done in stages.
First you find out exactly what bios you get, look at the revisions list, and go from there. There'll be notes on every revision.
This will have to be done with every motherboard that was manufactured prior to 3rd gen release, and PCPartPicker or any other site can't guarantee you get a motherboard with a current bios or one that's 2 years old. So all the 1st gen and 2nd Gen boards are subject to bios update warnings. The only boards that guarantee 3rd gen are the X570's and the upcoming B550's since they are 3rd gen boards.
Some manufacturers like MSI have designated a MAX version, specifically stating 3rd gen bios already installed or most will have a 3rd gen ready sticker on the box, donating they were manufactured after 3rd gen release and have a 3rd gen bios. Other than those, you'll need to update.
With your conditions, any mobo will do, as long as it fits your case, and your needs. No point in going with mATX if you have an ATX mid tower and more than 2x 3pin case fans. For example. It would also help if the motherboard output for video also matched or could match your monitors requirements, if planning on using a discrete gpu, I'd not bother with any of the 'G' APU's, a R5 1600 AF will be far superior and cheaper.