I am extremely skeptical that it will only cost few cents. (I've sent and received BTC in early 2010s)

On ramp and off ramp to fiat will kill you - whether through transaction fees or through slippage.

Let's say I am in US with 10k USD cash and I want a family in Ukraine (let's say somewhere safeish like Lviv) to have that 10k USD in hand.

Crypto is going to be more expensive than Western Union/Transferwise/SEPA/regular bank transfer/courier through friends.

That is the problem with crypto transfers - sure most crypto coins can be transferred cheaply.

However that "cheapness" only works as long as you stay in crypto verse.

I mean there is no way you can get them USD as cash in hand if that's what you mean. Do you mean USD as in a multi-currency bank account like revolut?

Onramp via onjuno, convert to USDC, send to your polygon wallet, convert to jEUR on Jarvis, send jEUR to friends wallet, they offramp jEUR with 0 fees to their IBAN bank account in ukraine via mt.Pelerin.

You only pay the polygon token transfer fees here.

Times have changed since 2010!

i wonder if usdc to jeur is more efficient than usd to eur. it could be- many banks are opaque about their conversion rates.

Could be. Although USDC to JEUR is using chainlink feeds (which is aggregated data), but they do advertise 0 slippage.