if changes the recipe to require engine units. depot and drone are unavailable to craft.

table.insert(data.raw["technology"]["engine"].effects,
{type = "unlock-recipe",
recipe = drone_name})
table.insert(data.raw["technology"]["engine"].effects,
{type = "unlock-recipe",
recipe = "mining-depot"})

add option to change require tech or disable this requirement

sorry my english.

Yes, if the drones require engine units to craft, then they also require the corresponding technology. I did it this way because you would be unable to craft them before unlocking the tech anyway.

I could add a second option to disable this (can you tell me why you want this?).

Any mod remove engine tech.

Edit: Angel Industries probably
[engine-unit change to motor-2] (tier 2)
[engine tech change to angel-components-mechanical-x tech tree] (x = 1 to 5)

Ah ok, I didn't think of that. Maybe a small mod like this one shouldn't change technology requirements. Anyway, I added it as an option.