Well, maybe I'm a stupid idiot but I found them and they look like this :
<node id="Item">
<attribute id="Translate" value="0 0 0" type="12" />
<attribute id="Flags" value="9007216434627020" type="24" />
<attribute id="Level" value="" type="22" />
<attribute id="Rotate" value="0 0 0 1" type="13" />
<attribute id="Scale" value="1" type="6" />
<attribute id="Global" value="True" type="19" />
<attribute id="TreasureLevel" value="-1" type="4" />
<attribute id="LevelOverride" value="1" type="4" />
<attribute id="TreasureGenerated" value="True" type="19" />
<attribute id="CurrentTemplate" value="e676d5f0-8aa2-4a1e-4b93-6248fb6b7397" type="31" />
<attribute id="CurrentTemplateType" value="0" type="1" />
<attribute id="Stats" value="CONT_IO_Runes" type="22" />
<attribute id="Inventory" value="90071996842377569" type="24" />
<attribute id="Parent" value="90071996842377316" type="24" />
<attribute id="Slot" value="38" type="3" />
<attribute id="Vitality" value="-1" type="4" />
<attribute id="Armor" value="0" type="4" />
<attribute id="LifeTime" value="0" type="6" />
<attribute id="owner" value="18014402804449377" type="24" />
<attribute id="OriginalOwnerCharacter" value="18014402804449377" type="24" />
<attribute id="UseRemotely" value="False" type="19" />
<children>
<node id="ItemMachine" />
<node id="VariableManager" />
<node id="StatusManager" />
</children>
</node>
161 of them in total (7 characters) with CONT_IO I identified as from bag-mod. I will remove them or make them sellable and then would try to convert save-file back.
P.S. tag <children></children>, really Larian?