Can you really configure to send from the forwarded address? From the faq[0] page: "When you need to both receive and reply to emails from a custom address, and unlock other professional features, upgrade to Google Workspace."

[0]https://domains.google/learn/how-to-use-email-forwarding/

I've done it just fine without Google workspace and people get my mail just fine.

Can I do this for multiple accounts? Do you k ow if there is a description of this solution online somewhere?

There's a limit of 100.

https://domains.google/learn/how-to-use-email-forwarding/

Yes, but you have to manually set up each account (eg. name1@example com) you want to send mail from to verify that you own the account.

Would it work for others in my family, without me being able to read all their emails?

Yes, each email alias can be set to forward messages to a different address.

Does this prevent the whole custom@domain.com via name@gmail.com thing?

I'm not sure what you are talking about so I don't think it's a problem as my emails look normal in gmail and it doesn't show anything weird.

You might want to go over some of your email/message/security headers and look for anything unexpected (e.g. actual email address, device names, locations, etc.). The web-interface won't display most of what you'll find in there, with good reason.

Finding a way to access those headers from gmail will be a challenge though. Don't think I've ever found that button in the same place twice!

I don't think that this will enable you to send emails that conform to the DMARC standard (using DKIM and SPF). Might be ok for a side project, but in my opinion not enough for a small business.

Yes

That didn't work for me.

My domain is still set up with G Suite with SPF and all so Google is technically fully capable of sending emails on my domain’s behalf, but if I got the "me@example.com via example@gmail.com" text regardless.

My setup:

    1. log into example@gmail.com
    2. set up "Send as me@example.com" with alias
    3. enter example@gmail.com as the SMTP username

Headers:

    ARC-Authentication-Results: i=1; mx.google.com;
       spf=pass (google.com: domain of example@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=example@gmail.com
    Return-Path: <example@gmail.com>
    From: Me <me@example.com>

There's a special reason to use Google Domains or it's just an example? Don't most registrars have web forwarding and mail sending features?

I don't know other registrars offerings, but OP was particularly concerned about using Gmail (or something like it) and having good deliverability, which makes Google Domains + Gmail the right solution in my mind.

Which SMTP server do you use for sending? Are you able to use Gmail's SMTP servers with your setup?

Yes, gmail's. You set a SPF record authorizing it.

Plenty of people would rather stick to dealing with ICANN's pricing directly via CloudFlare.