This page gives a ton of info on how to change these things to fit your servers, I suggest you check it out:
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=602282568

The basics however are:

OverrideNamedEngramEntries=(EngramClassName="EngramEntry_NameOfEngram_C",EngramHidden=false,EngramPointsCost=4,EngramLevelRequirement=3,RemoveEngramPreReq=false)

- EngramClassName= EngramEntry_NameOfEngram_C <-- That "_C" has to be there!
- EngramHidden= True or False <--- False to SHOW the Engram; True to HIDE the Engram
- EngramPointsCost= How much does the Engram Cost in Engram Points
- EngramLevelREquirement= What Level do they get the Engram
- RemoveEngramPreReq= True or Fale <--- This removes the requirements an Engram has.

You can find all of my codes in this forum.

EXAMPLE: This should remove the requirement for the trike saddles.

OverrideNamedEngramEntries=(EngramClassName="EngramEntry_Saddle_Trike_NivSadEmp_C",EngramHidden=false,EngramPointsCost=0,EngramLevelRequirement=16,RemoveEngramPreReq=true)