All Ryzen CPUs support OC and you need to have either B350, X370 or X470 chipset MoBo. So, in that sense, you can go with any B350 chipset MoBo just fine.
B350 vs X370 chipset comparison:
https://www.gamersnexus.net/guides/2763-amd-chipset-comparison-x370-b350-a320
Though, do note that B350 and X370 chipset MoBos may need BIOS update before you can use R5 2600 in your MoBo. No BIOS updates needed for X470 chipset MoBos.
List of best AMD MoBos (AM4 and TR4 socket):
https://www.tomshardware.com/reviews/best-motherboards,3984-3.html
BCLK OC as such is a thing about Intel non-K CPUs where users want to get a bit more out of their locked CPUs, about 200 Mhz or so. As i already said to you in Discord, it was a thing back when Skylake CPUs...