I’m so glad I could help! 
Here are my thoughts on your combos:
[name]Annika[/name] [name]Wynn[/name] Belsh” – Still my absolute favorite. I think it flows beautifully, and I know it’s a name you love! With the Ahn- pronunciation, I doubt you would run into anyone who would call her [name]Annie[/name].
I also think [name]Annika[/name] is so beautiful paired with [name]Owen[/name]!
Eilonwy [name]Annika[/name] Belsh” – You know I love Eilonwy, and I do think it’s one of the most phonetic Welsh-derived names I’ve seen, but it can get to be a mouthful, especially with [name]Annika[/name] in the middle. Something about the repeated “Ahn” sounds throws me off, I think. However, [name]Wynn[/name] would be even worse with it, so I unfortunately do not think this is the best option.
[name]Isla[/name] [name]Annika[/name] Belsh” – The names blend into each other too much. If it was Isly/Ily [name]Annika[/name] it would work for me. You also seem to be someone who would like to shy away from popular names, and I think this one is going to get up there.
[name]Adalyn[/name] [name]Annika[/name] Belsh” – I like a lot of the other combos a lot more. Another thought-- [name]Adalyn[/name] may not escape being called [name]Addy[/name], in case that is a deterrent for you.
[name]Eloise[/name] [name]Annika[/name] Belsh” / [name]Eloise[/name] [name]Wynn[/name] Belsh” – I prefer [name]Eloise[/name] [name]Annika[/name], I think. It flows nicely but for some reason, I just like some of the other names better.
[name]Eliza[/name] [name]Wynn[/name] Belsh” – Beautiful flow!
[name]Ingrid[/name] [name]Annika[/name] Belsh” – I love [name]Ingrid[/name]! [name]Love[/name] the flow of this one too!
[name]Ione[/name] [name]Wynn[/name] Belsh” – Somehow this doesn’t flow for me, and I agree that it’s pretty tongue twisting with [name]Owen[/name]. There’s also [name]Iona[/name], and I think that would work out better.
Ottile [name]Wynn[/name] Belsh” / Ottile [name]Annika[/name] Belsh” – I assume this is pronounced like [name]Ottilie[/name]. I like it a lot, actually – very unusual but still very accessible… Ottile [name]Wynn[/name] is my preference between the two.
Okay so my personal favorites are [name]Annika[/name] [name]Wynn[/name], [name]Eliza[/name] [name]Wynn[/name], [name]Ingrid[/name] [name]Annika[/name], and Ottile [name]Wynn[/name], and although all of the names you and your husband agree on are fabulous, I’m throwing my full support behind [name]Annika[/name] [name]Wynn[/name]!
I’m eager to see how your list gets narrowed down next! 
Have a great day!