Official GT's package name is gregtech and yours is gregtechmod.

I have no idea if thats by design but this is causing crashes with other mods.

That causes all addons like CropsPP to crash due to a ClassNotFoundException, which is totally reasonable since that class just doesn't exist, as far as both the GT addons and java are concerned.

List of addons that I could find that were affected

1 - ⚠️ ❌ CropsPP
Reproduction:

• Place any vanilla sapling into a IC2 Crop.
• Right Click at any stage of growth.

Code path:

// com.github.bartimaeusnek.cropspp.crops.cpp.Bonsais.java
@Override
public ItemStack getGain(ICropTile iCropTile) {
        int max = 0;
        for (int chanch : chanches) {
            max=Math.max(chanch,max);
        }
        // ClassNotFoundException: gregtech.api.objects.XSTR
        XSTR rand = new XSTR();
        
        int roll = rand.nextInt(max);
        for (int i = chanches.length - 1; i >= 0; i--) {

This one is specially worse, since the XSTR class doesn't exist on the project, so even if there were a way to redirect the call to your mod, it would fail.

It is of note that I was going to publish that on the Lost Era Modpack's Issue Tracker but since this a problem that involved a cross-mod compatibility issue that's more technical I've decided to put it here instead.