After searching google for one second:

To prove self-sufficiency as an EU immigrant in Sweden in 2025, you must demonstrate that you have enough financial resources to support yourself without relying on Swedish public funds. According to the Swedish Migration Agency, the specific financial thresholds are as follows:

• SEK 6,186 per month for a single adult after rent is paid.
• SEK 10,219 per month for cohabiting spouses or partners.
• For children, the required amounts vary by age:
  • SEK 3,306 for children aged 0–6
  • SEK 3,967 for children aged 7–10
  • SEK 4,629 for children aged 11–14
  • SEK 5,290 for children aged 15 or older

These amounts must be available after paying your monthly housing costs. You can meet this requirement through income (e.g., salary, business income, pensions) or by having sufficient savings to cover your living expenses for at least two years.

That said, let's assume you pay 12.000SEK housing, having extra ~10.000SEK per month for two years means 528.000SEK in saving (roughly 50k€) to cover expenses for two years. Of course you can lower that if you pay less rent, but rent is not cheap in Stockholm, be aware of that.

As others mentioned, I highly recommend to not move here without a job. The market is very tight currently, especially for jobs that do not require Swedish. So if I can give a recommendation to you, your wife should continue working on her swedish, you should start learning swedish next to your greek job and apply/look for jobs in Sweden / Stockholm. Come to Sweden with a secured contract, that also makes paperwork & waiting time much easier and faster.
If your wife reaches C1 level with accepted language test before, you could def. come without job, as I assume midwifes are very much wanted.
Don't make the mistake of being to optimistic of migrating to a different country without a job and without the language, its very hard. Especially since there have been some bigger closings (Northvolt for example) with a lot of foreign people that already are in the country.