The problem with catch-all inbox is when you have to reply to an email. Then you have to create the email address to be able to send emails from it. Or are there other solutions?

When you reply, any sensible system will use the address you received it at. Fastmail does this, as do many others (I used Thunderbird for many years, possibly with an extension to do that). To send an email from scratch you just type the address you want in the from field or select from a list. At no point is there any need to create specific addresses, as the catch-all means all addresses are already valid.