Context matters, this sub thread (and the title) is about Regexes.

If you think the OP is asking an XY question you should reply to him directly, IMHO.

Generally speaking: Yes, of course you can always replace time complexity with space complexity (preprocessing input data).

But it doesn't add much information to a Regex discussion.

I'm wondering who in this thread even bothered to understand what trie optimization does. It's not that complicated...

Edit

And it's actually very close to the way data is preprocessed.