There were some cool Mods that enabled nude woohoo, Teen marriage, Teen pregnancy (Teens could marry and impregnate YA/adults/elders and vice versa), Romance and marriage enabled for all ages except children, same sex pregnancy, incest, polygamy and much more...
All these don't work under "The Sims 4 fix" (1.13.104.1010)...
Is there any chance to have all these back?

Try this one.
http://sexysims.info/download.php?t=175128
You'll need the Command Center which is available at Mod the Sims. It's easy to use and does what you're asking for. There are also other modules at MTS. The Woohoo is just here because of the nature of the mod.

Baby, you rock...!!! Thanks a lot...

I have installed the "MC Command Center" on the "1.13.104.1010" fix and configured the game accordingly. All seems to operate smoothly...
But when my Sim clicks on an other Sim and chooses "MC Command Center" some times I get a menu with the commands as follows...
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Forget active Sim
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Modify in CAS
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Set Age
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Sim Commands...
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Sim Flags
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Mark for Move in
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MC Pregnancy...
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Cancel
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By clicking on "Sim Commands...", I get a second menu with the following commands...
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Delete Sim
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Kill Sim
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Transfer funds
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Set active relationships...
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Alian-ize Sim
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Back
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Cancel
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But some times, by clicking on "Sim Commands", with another Sim, I get another menu with the following commands...
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Modify in CAS
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Set Age
---------------------------
Sim Commands...
---------------------------
Sim Flags
---------------------------
MC Pregnancy
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Cancel
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By clicking on "Sim Commands...", this time, I get a second menu with the commands as follows...
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Everyone forget Active
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Everyone forget Active all
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Alian-ize Sim
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Back
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Cancel
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In this case, in this second menu, I do not get the " Set active relationships..." command...
What am I doing wrong...? Please...

There are pretty detailed explanations at MTS

@ Tatiani1990 - Your question would be better answered if you post it in the Comment section of the download page for MC Command Center at MTS: http://www.modthesims.info/download.php?t=551680 People are much more active there than here.

Thanks a lot, pals...

I am from germany. Therefore our patches aren't as far as. My question now... My patch is 1.13.106.1010 and I would need Mc Command Center and Mc Wohoo that work with that version of mine. Is there any way to get a hand on those?

You can get the updated files for the MC Command Center from Mod the Sims: http://www.modthesims.info/download.php?t=551680
The update risky woohoo mod for MC Command Center is available on this site.

Thank you for your reply, FLChicago ...well those are the versions for 2.3.0 are they going to work for me too as I have only 1.13.106.1010 and I am only having Sims 4 + Get Together added. In germany we have only those two released yet.

From the change log: Changes from version 2.2.2 to 2.3.0 (Sims Version at time of release was PC Version 1.13.106.1010 / Mac Version 1.13.106.1210), so it seems Germany is patched to the same version as the US

Been meaning to let you guys know what was my problem why the Mod didn't want to work for me. You need to, OF COURSE, place ALL in the mode, not just packages of the woohooer but also their scripts. I had just the package of the whoohoo and the comand center in it but didn't put the scripts in it because I was thinking you need just either package or scripts... let me tell you... for future reference.... you need to put in all of the content of the zip file into the mods folder or it will not work. Now it works for me and I am happy. Thank you