Don't get me wrong, I like IBKR and I do use it, but Transferwise is definitely more useful 90% of the time.
It's still mind-blowing to think IBKR charges $20 per million, when the airport Travelex will charge you $20 per hundred lol.
You'd open up a trading account, deposit funds from one country to it (generally free in EU/UK, can be done with a simple bank transfer, though can take 1-3 business days). Rather than the common use case of a brokerage account to buy stocks/invest, you place an order into their IdealPro order book they run to buy the currency you want (might have to jump through 2 trades, they don't run every single pair). Generally this is tailored at larger investors, so anything under $25k is subject to some additional fees due to being a small size (https://ibkr.info/node/1459), but still significantly less than the 0.35% TransferWise charges. The costs for you are commission (<0.2bps), potentially small size fee (1-2 bps), and crossing the bid/ask spread, which is ~0 for currencies). When that order has been filled you now have the desired currency in your account and you can transfer it back out (potentially to a different country or different account).
It's a free/cheap multi currency account with local bank details in 6+ countries, which give you 90% of the functionality you want, namely the ability to hold and transfer cash.
If you need more functionality you get a local bank account.
You are too young :-). This also might change. German banks start again to take monthly fees for accounts, so why not for single transactions.
This said, I have to deal with accounts in NZ and Europe. Fees as well as speed for transfers between them is a whole other world when using TW compared to classic banking. These kind of costs have exist forever, SEPA conditions are the exception, not the rule, internationally. TransferWises multi-currency account is a nice part of the package. I learned here today, this can be done even cheaper by using a Forex broker like IB, but I don't need this on a daily basis.
EDIT: 32p - https://transferwise.com/gb/pricing/borderless-send?source=G...
I apparently have to pay €0.28 per transfer in EUR with Transferwise. There are competitors (both in CHF and in EUR) that do this for free. I do something like 8 transfers per month, so that's 8*0.28*12 = €26.88 per year, for no added value. Not convincing.
their ACH fees does seem a little more expensive
That’s a dealbreaker for me, but I’m a happy customer of theirs for transfers.
e.g. I'm opening an account in France at the moment (as a French resident!) and it is taking literal weeks and lots of scanning documents, posting paperwork, phone calls etc. TW opened a Euro account for me in a few clicks.
I remember the app used to show two sets of US bank details, and that the routing number for receiving wire transfers was different from the one used for receiving ACH transfers. But that seems no longer to be the case.
I know if the ownership details don’t match up exactly there are extra steps, but it was pretty painless for me.