Recently got rid of inteen here. I've got almost everything replaced now I think except for these ones. Been looking on google for about an hour now and can't find anything other than the hacked wedding arch. Which is fine too it's just not what I'm looking for.
I manage to do all of these using a variety of mainly old mods. My highest EP is Open for Business so so I use several mods which probably wouldn't work if you have the higher EPs. For Engagement and Marriage, I temporarily age one of the teens up to Independent Teen using the Sim Manipulator. Afterwards I age them back to ordinary teens using the same tool. It does result in them getting a lot of new clothes, and, with a little bit of luck, you, or they, might actually like some of them. I have Jenflower's Woohoo Teens, which is another old mod (I got it Simbology), but it makes teens act more like adults. Without it, I'd almost certainly have to age both teens up to Independent Teens. With it I only have to age up the one doing the proposing; the other one will accept, providing their relationship is good enough. There are more modern alternatives to Woohoo Teens (I know of one called "Wild Child") which are compatible with the later EPs, but I don't know if they'd enable a teen to accept a marriage proposal.
I could move teens in and out by temporarily aging them up with the Sim Manipulator, and I used to do this, but I now use a mod Move In to all sim ages v2 [OFB Only] by pinhead. This though is specific to people like me who's highest EP is Open for Business. I don't know if this was ever updated for later EPs. Pinhead also wrote a "Find Own Place" for Teens mod. Versions of this one were made for EPs up to Seasons, but again I don't know if any later versions were made.
I appreciate that these versions I've linked to probably won't do the job for you, but maybe someone knows about newer versions of them, and can post here. If all else fails, you can always age up to Independent Teen with the Sim Manipulator, and then age back down again. Insimenator and the Simblender might be able to do the same, but the Manipulator is the one that I use.
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