Former Elf Companions Joining Solas (or not) In DA4

Yes, and through that transcript, we can see that her changes are far from non-existent or really that ambiguous - it's only your interpretations that try to make them so. The major issue I see is that it seems that Cassandra simply isn't fast or radical enough for your taste (and I say so as someone who usually makes Leliana Divine), or she isn't the one who believes that institutions within the Chantry have to be completely torn apart or forced to change in a heartbeat in order to be thoroughly reformed.

The reality is that she ultimately still wants to change the Chantry in the very same direction Justinia and Leliana want them to - which is why she accepted Justinia's offer to become her Right Hand, or why they work together well with Leli, even if Leli is the Divine. If you read her opinion about supporting Leliana as Divine it's clear as day that the difference between her and Leliana is not that she wants to keep things how they are - far from it - but that she thinks that being too hasty with change will result in chaos or can backfire spectacularly if things are too fast for people to accept them (a factoid supported by her own epilogue slides as Divine in the main game, specifically mentioning that some think that she's going too far with reforms, duh).

To put it simply, she's the pragmatist in this duo of Hands - someone who, if we choose her as the Divine, offers a path of steady reform in any world-state she is Divine (in contrast to status-quo-protecting Vivienne), instead of more risky Leliana whose state of her personal quest determines her rule as the Divine.

DUH.

I've yet to be convinced that Cassandra shows any signs of studying Tranquility in the 4 years she has the knowledge or that this will suddenly change later.
I said it was possible that DA4 could go back and say that she did. My opinion would then be slightly adjusted. But that is an assumption of what DA4 will retroactively change/add about Cassandra and her actions over the 4+ years since she's had the information and the start of DA4. I will not make that assumption. I will have my opinion based on the information I have now. And that's that she did nothing with the info and other than a few dialogue lines in her personal quest about how it made her ashamed of the order, hasn't cared to mention it since.

Therefore, I don't see her, or anyone on the Good People Side, choosing to Un Tranquilize Avexis in DA4. So I still believe that if anyone would, it would be the Bad Guy Side.

That's a narrative that's interesting to me, an elf that has special powers that would support Solas with knowledge of the outcome.

She could also not show up at all and be a weird movie-sourced cameo of a cool little elven girl who was effectively punished for being unique in the current Veiled world of Thedas.

Done. I don't care to spend my energy anymore on it. We got till Fall 2020 before we even get the game, I probably won't even remember I made the suggestion by then.

I just remembered about another group - Elf Werewolves.

I've only skimmed through this thread, just enough to see that there was talk of Fenris possibly joining Solas/ agreeing with his plan...

I saw David Gaider's tweet, and I definitely think that it was dripping with *sarcasm* (this is Gaider we are talking about after all). He even placed a winking emoji at the end of it.

Fenris would be completely against Solas' plan. Why on earth would he want to Veil to be destroyed. He hates magic, hates demons, and feels no kinship whatsoever with other elves. There is no way he would willingly go along with it.

I can see some companions inadvertently helping Solas assuming he uses different cells for different purposes. Example: 1 cell will be about helping and freeing (elven) slaves which is something that Fenris will do. Another will be about procuring ancient elven artifacts and knowledge which is something that Merrill might be interested. An agent can potentially hire Zevran to kill troublesome people. While on the surface, these cells might seem to be working for different goals, in their all being used to further Solas plans.

Merrill, Valanna, and Fenris would all join Solas in a heartbeat. They might have some reservations about his methods, but they would agree with his end goal. A free elven empire ruling the world.

Even Zevran might be on board... but for him it would depend on how close he was to a non-elf Warden.

Tallis and Sera are the only elves would wouldn't join.

He cares about elves being free, by force if necessary. Solas is the answer to this.

If Fenris was in favour of this then he would be a total hypocrite. He is against magic, full stop. So why would he aid Solas in restoring a world with a free flow of magic? If he heard that the Veil was created in the first place to trap all powerful tyrant mages and that dropping it would free them, why would he want to do that? Merrill wanted to restore the eluvian to help the elven people but he was thoroughly against her and that wasn't simply because she used blood magic to achieve her aims. Anders didn't want to use blood magic but Fenris was against him because he wanted to give mages more freedom. If Fenris knew the Viddasala had been trying to strengthen the Veil, I think he'd more likely have supported her.

There are other ways of achieving freedom for the elven slaves that wouldn't involve flooding the world with magic. So unless Solas or his agent were very careful in concealing the real intent from Fenris I don't think he would knowingly support the schemes of Fen'Harel, an ancient elf mage god.   Remember just saying we would restore the world of the elves might flag up danger signals to him since the Dalish constantly teach that once upon a time all elves had magic.

Same with Merrill.