Ohtani has four less HRs than Andujar (19 to Andujar's 23). In 250 less ABs. Ohtani's OPS .946 to Andujar's .851. Also, has a 3.31 ERA as a starting pitcher, 11.9 K/9, and a 1.161 WHIP.
Andujar will win ROY, but he isn't the better player, and it could be argued his season is less spectacular (it isn't debatable for me, but I will give Yanks fans the benefit of the doubt). His saving grace is playing for MFY - a sure fire contender this year, having a solid season, as well as picking up the slack when Judge went down, and Ohtani's injuries. But if Ohtani keeps raking this September, the BBWAA will look hard at him.
Ohtani has had a more sensational rookie season, when he's in, and it isn't even close. Has hit 3 HRs since his third UCL tear.