Im missing a lot of charm that w2 and first starcraft games had, and i did not see any open engine recreations, nor clones that lived to this day. With warcraft 3 i only ever finished half of the game, by the time sc2 came out, i was already too old to even bother trying.
Ground Control is does not feature the base-building of WC/SC, but are excellent RTS mission-based games.
Homeworld: Deserts of Kharak is another excellent one.
Earth 2150 includes the base-building, as well as a very cool “persistent homebase” mechanic for the singleplayer campaigns, where you build bases in the mission sites but also have a home base that you can transport units to/from, for use in future missions.
I would add the 1999 game Warzone 2100 to this list. Much like Earth 2150 you can design your own units and it also has the persistent homebase + mission outposts system. It was open-sourced in 2004 and has received quite a bit of love since then.