Need some help refactoring list comprehension

These are not list comprehensions, but generator expressions being fed to sum. Frankly I don't see a clear path to further simplifying the code, although I guess you could use this if you really wanted a one-liner:

total_score_p1, total_score_p2 = [sum(scores[x] for x in raw_data) for scores in (scores_p1, scores_p2)]

Worth noting that I do prefer

total_score_p1 = sum(scores_p1[x] for x in raw_data)
total_score_p2 = sum(scores_p2[x] for x in raw_data)

as a more readable option.

Just a side note about your full code: You never close the file! And you can't because you do not have a file handle. Your desire to write one liner is preventing you from doing it properly. It's ok to lay down a few more lines to make it proper and readable. It's actually way more "pythonic".

same but i kept them as separate methods in a class.

class Day2:
    def __init__(self):
        with open('day2.txt', 'r') as f:
            values = f.readlines()
        self.value = [value.split('\n')[0] for value in values]

    def day2_2(self):
        table = {'A X':3,'A Y':4,'A Z':8,'B X':1,'B Y':5,'B Z':9,'C X':2,'C Y':6,'C Z':7}
        return sum(table[i] for i in self.value)

    def day2_1(self):
        table = {'A X':4,'A Y':8,'A Z':3,'B X':1,'B Y':5,'B Z':9,'C X':7,'C Y':2,'C Z':6}
        return sum(table[i] for i in self.value)

If you want a single iteration you can:

>>> moves
['A Y', 'B X', 'C Z']
>>> [[score[move] for score in scores] for move in moves]
[[8, 4], [1, 1], [6, 7]]

zip(*) can be used to turn it into:

>>> [ *zip(*[[score[move] for score in scores] for move in moves]) ]
[(8, 1, 6), (4, 1, 7)]

Which you could then sum.

>>> totals = ([score[move] for score in scores] for move in moves)
>>> p1, p2 = (sum(total) for total in zip(*totals))
>>> p1
15
>>> p2
12
>>> p1, p2 = map(sum, zip(*([score[move] for score in scores] for move in moves)))
>>> p1
15
>>> p2
12

Another way is to use operator.itemgetter()

>>> from operator import itemgetter
>>> p1, p2 = map(sum, map(itemgetter(*moves), scores))
>>> p1
15
>>> p2
12

I don't see a problem with your original approach - it's much easier to understand.