I pretty firmly believe this is their problem and shouldn’t be yours, and probably won’t be a universal or “confusing” problem for most. I dislike phonetic variations to make things easier - people who are unfamiliar with “[name]Michaela[/name]” and think that it’s supposed to be [name]McKayla[/name] are in the wrong. They don’t even know where the name comes from, they are just playing with random sounds - if they think [name]Michaela[/name] is [name]Michael[/name]-ah, and don’t recognize it, then [name]Mikayla[/name] is not very clever. I wouldn’t want a name that so far deviated from its origins that nobody even thought it was the same name.
Please use the real name if at all. To do otherwise is to obscure and dilute the true name — I’m not so harsh about spelling variants as some others but I do have my buttons to be pushed sometimes. If you love another spelling, that’s your choice. If you have another reason, like making it easier for people to read, then it’s better, in my opinion, to stay true to the name and allow people to remember it and learn about it, and like a lightbulb actually make the connection. Not too many people will be confused though.
I think Mikaylas and all the crazy spelled ways of it are quite common actually, meganame wise not to mention plain [name]Kayla[/name] (and any weird spellings of it). Maybe no two spell it exactly the same way, but on balance there are probably fewer Michaelas than the malformed/uninformed versions. If you have to go with a meganame, I really like [name]Michaela[/name].
If you are Ukrainian, how about MYKHAILA? It is strange how the name morphs so nobody even recognizes it, while trying to make it faux Irish ([name]McKayla[/name], son of [name]Kayla[/name]?) or faux Russian ([name]Mikhaila[/name] = invented!) and losing any semblance of [name]Michaela[/name], you can be authentic with a crazy spelling also. Some of those variations hit on an authentic foreign variation - maybe some intentionally, even. Strange but true.
I also have to say, I still like [name]Michelle[/name]. Others will say it is dated. I think it is a “classic,” but like [name]Patricia[/name], went out of style to make room for other classics that were not really fashionable in the 1960s, 70s and 80s but are now. I like classic names, but some of them stay on top and the rest sort of change places with each other every decade or so. [name]Michelle[/name] is at 103 last year, peaking about 40 years ago at #2 (debuting 1938). Decades of heavy use make it sound less special, but it’s still pretty and feminine, and I think, firm, classic choice.
[name]Michaela[/name] may be the “true form” but even with all those Michaels, I never once met a [name]Michaela[/name] (I mean around my age). I’m not sure how stylish it has ever been prior to now - according to the SSA, it has enjoyed slight but increasing usage from the late 1960s forward, debuting on the chart in 1967, and peaking at 100 in 1997. So, in effect, it’s also kind of dated, and lumped in with all the variants, some of which are also declining and some not - [name]Makayla[/name] went 10 spots up last year.
I think the [name]Michaela[/name] spelling will transcend the time-stamp a lot better. It’s still a light pretty sound while appearing serious and capable. I can’t imagine an adult [name]Makayla[/name] (the most popular spelling, I think) handling any important tasks. It’s so phonetic, it seems juvenile. Not that a lot of names aren’t easy to read, naturally, but if someone doesn’t know how to say a name, I would spell it phonetically for them, but I would not expect them to use that spelling!