Most accurate gb/c emulator and does it support sgb features?

Libretro Cores
#1

Is sameboy, gambatte or mgba more accurate for gb and do any of them support sgb borders and colors other than mgba?

#2

I know for an fact that Sameboy is most accurate and Gambatte supports colors.

#3

I’m pretty certain Gambatte doesn’t support any SGB features including expanded palettes. BSNES does but only on platforms that support command prompt arguments.

#4

Probably BGB but there is no core for it. (Closed source).