BA has details on how the international draft could work, such as hard caps and rotating top 5 picks (by division)
More at the link.
Based on what MLB told team personnel yesterday, the most recent draft concept would be 20 rounds, with teams allowed to trade picks. Every pick would have a hard slot value, so if a team drafts a player and the slot value is $1 million, that player would sign for $1 million. Picks in the top three rounds would be protected for clubs, so if a team drafted a player in one of those rounds who didn't sign, it would potentially receive compensation in the following year's draft.
After the 20th round, teams can sign nondrafted free agents for up to $25,000. The age when players become eligible to sign would still be 16. However, while the current system centers around July 2, the annual opening of the international signing period, the draft would be held in August.
https://www.baseballamerica.com/stories/mlb-targeting-international-draft-as-soon-as-2020/One of the bigger twists in MLB's latest draft concept is the draft order. Instead of replicating the order of the June draft, which would reward the team with the worst record the previous season with two No. 1 overall draft picks, the teams picking at the top of the draft would rotate annually by division. So one year, for example, the teams in the National League East would get the top five overall picks. The next year another division would get the top five picks, and it would rotate every six years.
More at the link.