DD now has this feature available for all Make Offer marketplace listed domains.
It is a little unwieldy to set it up for hundreds or thousands of domains. To do this, you must go to My Domains / Manage Domains
so that 100 domains are showing per page (the maximum).
Then, filter For Sale / Marketplace
Now select all 100 domains by checking the box to "select all" down the line, and Bulk Action / Sell Domain
and set for Marketplace
and you will see this screen
where you may set a minimum (in this case 1000) for all 100 domains at once.
Click Save Settings, and one page of 100 domains will now be set for this same minimum offer of 1000.
Move to the next page, repeat the process, and again 100 domains at a time will be set to the requested minimum offer.
After you are done, you'll need to scroll back through all your domains again, one page at a time, because this process tends to miss some domains along the way, and set these domains too for the requested minimum offer.
At the other end, in the marketplace, I did not observe this minimum offer in place,
but I assume that the system prevents potential buyers from submitting any offer below your minimum.
As you go along and do this process, if you bulk select 100 domains at a time, full pages, this will overwrite any BIN prices on your domains - the DD system allows minimum offer only for Make Offer Marketplace domains, not for BIN set price domains. So, if you want to retain your BIN prices, you'll need to uncheck carefully any such domains from this Make Offer / set minimum price process along the way as you are bulk selecting pages of domains at a time.