Here is an argument against eternalism:
- If eternalism is true, times are like places.
- Times are not like places.
- So, eternalism is false.
- If presentism is true, times are like worlds.
- Times are not like worlds.
- So, presentism is false.
So how to break this impasse? One way would be to opt for a theory other than eternalism and presentism, say growing block. Another way is to keep on adding disanalogies between times and places or between times and worlds until one of the disanalogies ends up being much stronger. Yet another way, and I think the most promising, is to embrace both (2) and (5), but explain the disanalogy in a way that is compatible with presentism or eternalism (whichever is one's preference).
One should also note that arguments from analogy tend not to be the strongest.