How to scrape emails

Is it legal to send emails to these scraped mails without consent?

Sorry if I bring this up after a long time, but I figured it would make more sense rather than opening a new thread on the same topic.

Two question:

1. Talking email scrapers, how does Scrapebox compare to Hunter? Hunter is not cheap, but is giving me decent results in terms of emails verification. Is Scrapebox email grabber reliable too? Better bang for the buck?

2. I'm new to this and trying to find ways to improve email deliverability. Can you guys point me to a great guide on the forum here or elsewhere? Yes, I'm already using the search functioncheers!

I used few tools but for me the best one is salesql.