Possibly neither. Also, Earth-97 doesn't technically exist. It's a misunderstanding that caused that association. It's essentially become an unofficial number because of a joke about Batman & Robin's release date. The same logic could be used to say Superman IV is set on Earth-87, as that's the exact logic that joke was used in - a sequel is placed in another Earth because of it's release date. It wouldn't even work, because it would also be ignoring Batman Forever. Not to mention, the same "source" stated that Bat-Nipples are canon as a result of Earth-89, and the writer of Batman '89 can be discarded because the general consensus is that that comic takes place in Earth-789 of the comics Multiverse.
That is a completely unrelated issue, because whether The Flash film takes them as part of the history or not does not make Earth-97 "more" real. It either takes them as part of Earth-89 or it literally has no barring on any numbering for these films.
The point is Earth-97 doesn't exist, not anything regarding alternate sequels. Earth-97 is not a real number that has actually been officially stated by anyone with any authority or intent. The original joke was that Batman & Robin released in 1997, and thus, like Earth-89 and Earth-90, would have an Earth number reflecting it's release date. This wouldn't make any sense because Batman & Robin should be the same universe as Batman Forever, and in the same source they state that Bat-Nipples are canon because of Earth-89.
I'm frankly quite sick of that misinformation online, especially since Batman '89 apparently isn't even part of the film multiverse, so why do people care that someone mentioned this "joke" to the writer, who also made a "joke" because that comic was a different continuity?
We've actually gotten very little about that. The only time that has ever been addressed is indirectly in an article by one of the major trades (the same major trades that James Gunn is crapping on) and simply stated that they're ignoring those films.
A UK production company working on The Flash produced Batman & Robin logos and shared them on Instagram. When I commented about it, I presented two separate ideas in two separate comments:
1. It is an easter egg in Earth-89, thus, while they are not directly referenced ("ignored"), they do occur in the same universe.
2. It is for an alternate universe.
They liked serveral of the first type of comment and nothing of the second. Truth is, we don't know what is happening. The Schumacher films very likely could be a separate universe. The point is that Earth-97 is not officially "that" reality, and we have confirmations that they take place in Earth-89 - at least, the Pre-Crisis timeline.