Basic XML / Text reading skills.
Let's take some random skill.
<skill id="1139" levels="2" name="Servitor Magic Shield" enchantCostMultiplier="5" enchantLevels1="30" enchantLevels2="30">
<table name="#mDef"> 1.23 1.3 </table>
<table name="#mpTotalConsume"> 39 48 </table>
<table name="#aggroPoints"> 418 495 </table>
<table name="#enchantMagicLvl"> 76 76 76 77 77 77 78 78 78 79 79 79 80 80 80 81 81 81 82 82 82 83 83 83 84 84 84 85 85 85 </table>
<table name="#ench1Time"> 1240 1280 1320 1360 1400 1440 1480 1520 1560 1600 1640 1680 1720 1760 1800 1840 1880 1920 1960 2000 2040 2080 2120 2160 2200 2240 2280 2320 2360 2400 </table>
<table name="#ench2Cost"> 46 45 45 44 43 43 41 40 40 39 39 38 36 36 35 34 34 33 31 31 30 30 29 28 27 26 25 25 24 24 </table>
<set name="mpTotalConsume" val="#mpTotalConsume"/>
<set name="target" val="TARGET_PET"/>
<set name="reuseDelay" val="2000"/>
<set name="hitTime" val="4000"/>
<set name="skillType" val="BUFF"/>
<set name="isMagic" val="true"/>
<set name="operateType" val="OP_ACTIVE"/>
<set name="castRange" val="400"/>
<set name="effectRange" val="900"/>
<set name="aggroPoints" val="#aggroPoints"/>
<enchant1 name="magicLvl" val="#enchantMagicLvl"/>
<enchant2 name="mpTotalConsume" val="#ench2Cost"/>
<enchant2 name="magicLvl" val="#enchantMagicLvl"/>
<for>
<effect name="Buff" time="1200" val="0" stackOrder="#mDef" stackType="MagicDefUp">
<mul order="0x30" stat="mDef" val="#mDef"/>
</effect>
</for>
<enchant1for>
<effect name="Buff" time="#ench1Time" val="0" stackOrder="1.3" stackType="MagicDefUp">
<mul order="0x30" stat="mDef" val="1.3"/>
</effect>
</enchant1for>
</skill>
As we can see, <for> tag gives us original skill stats. Original buff time is 1200 (time="1200"). This stat is modified at your version.
<enchant1for> gives stats update for already enchanted skill. It gives stat depending on enchant level (time="#ench1Time"). We need to check #ench1Time table to adjust time.
It is here.
<table name="#ench1Time"> 1240 1280 1320 1360 1400 1440 1480 1520 1560 1600 1640 1680 1720 1760 1800 1840 1880 1920 1960 2000 2040 2080 2120 2160 2200 2240 2280 2320 2360 2400 </table>
There you should manually change all times (in seconds ofc). When you will change this, enchanted buffs will be longer. This consumes much time, but... Good luck
