She’s here - rhymey?

I don't think it's a given that she'll get called Alex. These days she's more likely to get Lex/Lexi/Lexia I think, based on girls at the school where I work. I think if you call her Sasha from the beginning that also means she's more likely to stay a Sasha.

Kristina and Irina do sound quite rhymey to me, but not sure it's a total deal breaker.

I think it might be worth considering whether the two names are easily confused when called from a distance. It sounds slightly random, but we had neighbours, two of whose children were called Jude and Luke, and they said they’d never have chosen names that sounded so similar when shouted up the stairs, because all the kids heard was a vague ‘oo’ sound, and both always claimed they thought the other one was being called and ignored the summons!

It does rhyme but it seems to be the name you love the best, so in this instance, I'd say go for it :)

Irina is fine with your other girl's names, I don't think the slight rhyme is too twee or gimmicky at all. Especially with the differences in their ages etc. The meaning of Irina is beautiful. Go with what your heart is telling you!

I love it, but it is too rhymey

Alexandra nn Sasha?

Alexandra nn Sasha is absolutely gorgeous ❤️ and I think easier for Brits to understand.

The only thing I'm not sure about is that Sasha is a male name in Russia/Eastern Europe, I thought? I prefer it for a girl as I think it's quite a soft sound but will people think she's a boy? Not that it is a major concern, Alex is also unisex.

Alexandra is my favourite!
Congratulations!

If you start Sasha as a used name early on they it should stick so Alex won’t be used. If you just use Alexandra then then there is a good chance it may become Alex.

Irina is lovely, not too rhymey in my opinion.

I’m an Alexandra, known as Sasha. I’ve grown up in the UK and find the name a hassle tbh… Despite, I’d have thought, not being that unusual where I live / work (relatively cosmopolitan areas) I always ends up giving my life story as Brits don’t tend to have heard the diminutive before.

I’d go with Irina, which is gorgeous and on my list for DC3!

Alexandra nn Sasha is lovely. You could have the former on the birth certificate and inform school they are "known as" Sasha.

Alexandra definitely.. Irina is a bit awful old ladyish...

I remember your post and I would still say Irina is the best option.

Both lovely options. I don't think pronunciation would be a problem for Irina, not once she's been introduced. Not do I think Alex would be a problem. As others have said you'd just introduce her as Sasha wouldn't you. My dd has an uncommon diminutive and was never called anything else until secondary school and was given a new diminutive by her school friends. She now has several different names depending on who she's speaking to!

I always think of a shame that we have such fixed ideas about shortenings/diminutives in England, I much prefer the Russian way of there being a hundred different diminutives for every name, half of which have no resemblance to the name at all!

Alexandra / Sascha 👍

Alexandra is gorgeous and goes well with the other two. You won’t get Alex as a nickname if you get in first with Sasha (which is lovely also!)
I know an Aleksandra who has the nickname Ola, which is lovely too and has never been called Alex

People always make too big a deal out of things like rhyming names, alliteration, number of syllables in each name etc. In reality, no one will notice or care that the sisters' names rhyme. Or at best they'll say "Kristina and Irina, just noticed that rhymes" and then think about something else. And sibling names really don't need to "go" together at all - they'll be spending the majority of their lives apart anyway.

I love Alexandra and Sasha as nickname.

I love Irina. On my only ever visit to Russia I met a wonderful Irina and I've always loved it since. I do think it's too rhymey though!

Alexandra is beautiful and Sasha is lovely. I know a few Alexandra's who are Sasha and never get called Alex. I think the trick with that is to introduce her as Sasha. If you say 'this is Sasha', no-one is going to start calling her Alex.

If you're open to more suggestions the following names might work.
Isabella. Victoria. Natalia. Anastasia.

Irina is lovely but it is a bit rhymey with Kristina. I don't think its a particularly problem though. Do you not like Irena (Iraina) which is similar to Irina but not too close to Kristina.
If you don't like Alex then forget Alexandra. You may not intend for it to be shorted but what if she decides she herself wants to be known as Alex. You won't be able to stop her, it's name.

Congratulations! You could just about get away with it but Alexandra goes so much better. I don't think Alex is inevitable. If you only ever call her Sasha for short, others will follow your lead. I taught a lovely Russian girl called Sasha who was technically Aleksandra but we only ever called her Sasha.

Alexandra is nicer