Though I know there already is an option that requires the players in the same UI to spawn the neighbourhood base.
But is it possible for me to let the new player spawn near my base without resetting my base...?

Which is not sharing the tech and having his/her own resource, like the neighbourhood base.

Yep, someone else requested this too... I can definitely look into it, but no promises. I'm still trying to support separate landing sites for everyone on other planets. I'll make a ticket on my github repo to track it. Thanks for the suggestion!

Also, let me know what you mean exactly. Like is it okay if they just spawn in the nearest available area to your base (which might be 25-50 chunks away)? Or you want to create the buddy spawn exactly where 2 spawns are right next to each other, almost touching?

In my case, I usually tend to create the buddy spawn exactly where 2 spawns are right next to each other, almost touching.
Because I set the game difficulty is quite high. I want to have a game experience that is similar to Rimworld, which together defends against some attacks :P

Ah yeah, if you want to spawn right next to each other, I can't do that after you have already spawned. I could only do the closest ungenerated area, otherwise it is very expensive to search the map for an area to place the spawn that doesn't have player buildings.

If you want to play that way, right next to each other, you need to both start at the same time. I can still add a way to spawn "in the closest ungenerated area" to someone though since that search isn't as expensive.