In terms of gaming performance the results are an even split, but in most other applications the 4900HS is the clear winner:
The 4900HS posts 11.9% higher CineBench R20 score (both chips are 8-core/16-thread) when the Intel chip is bolstered with 90 W cTDP, and a whopping 33% faster when the i9-9980H is at its stock settings, and 54% faster when its capped at 35 W cTDP. It also ends up over 150% faster than AMD's last fastest mobile processor, the 12 nm "Picasso" based Ryzen 7 3750H. The story repeats with CineBench R15 (4900H being 34% faster than stock i9-9880H), 18% faster at Handbrake HEVC, 25% faster at Blender "Classroom," and 35% faster at 7-Zip benchmark. The AMD chip lags behind by 12% in the less-parallelized Photoshop. On creativity apps that do scale with cores, such as Premiere "Warp Stabilizer 4K," the 4900HS is 12.6% faster. Gaming performance remains an even split between the two chips.