Let's Go will get over 80 because sites that award their score out of five will not want to make the grand statement of giving it 3 rather than 4. I'll guess 83. Hard for it to go higher because critics will want to reserve headroom for the “real” Pokemon game next year.
Smash Ultimate will lose points over its single player. I'll guess 91. If it noses under 90 that will be real bad news.