How can I deserialize the object, if it was moved to another package or renamed?

It is possible:

class HackedObjectInputStream extends ObjectInputStream {

    public HackedObjectInputStream(InputStream in) throws IOException {
        super(in);
    }

    @Override
    protected ObjectStreamClass readClassDescriptor() throws IOException, ClassNotFoundException {
        ObjectStreamClass resultClassDescriptor = super.readClassDescriptor();

        if (resultClassDescriptor.getName().equals("oldpackage.Clazz"))
            resultClassDescriptor = ObjectStreamClass.lookup(newpackage.Clazz.class);

        return resultClassDescriptor;
    }
}

This also allows one to ignore serialVersionUIDs mismatch or even deserialize a class if its field structure was changed.

Question: Is it possible to load the new class instances from this file using any tricks (except trivial copying the class into old package and then using the deserialization wrapper logic)?

I don't think there are any other "tricks" you could use that don't involve at least a partial reimplementation of the serialization protocol.

Edit: there is in fact a hook that allows this if you control the deserialization process, see the other answer.

It is possible to use readResolve() to recover from moving/renaming the class? If not, please, explain why.

No, because the deserialization mechanism will fail much earlier, at the stage where it tries to locate the class that's being deserialized - it has no way of knowing that a class in a different package has a readResolve() method it's supposed to use.