Scoring during the playoffs is similar to scoring during the regular season. The big difference in standard league playoffs is that each playoff round lasts two (2) weeks, not one (1) week as in the regular season.
Since we do not reset the score to 0 after the first week of a 2-week playoff matchup, your Week 2 scores will be added to the first week’s score for a running total for the 2-week scoring period.
The ESPN scoring projection for the matchup is based on the current week’s projection + the second week’s projection, which is why it’s so large in comparison to what you may be used to seeing.