When paramatma can control his own souls why does he fight with weapons ?
The concept of God is Abstract.
However, different people understood it differently, and expressed their expressions according to their perceptions.
When Arjuna asked Sri Krishna to show his Divine form - द्रष्टुमिच्छामि ते रूपमैश्वरं पुरुषोत्तम, Sri Krishna says as follows:
इहैकस्थं जगत्कृत्स्नं पश्याद्य सचराचरम्।
मम देहे गुडाकेश यच्चान्यद्द्रष्टुमिच्छसि।।11.7।।
Now behold, O Arjuna, in this, My body, the whole universe centred in one including the moving and the unmoving and whatever else thou desirest to see.
And, what did Arjuna see? He describes the Viswavupa as possessed of numerous arms, bellies, mouths and eyes; as having infinite forms all around.
किरीटिनं गदिनं चक्रिणं च
पश्यामि त्वां दुर्निरीक्ष्यं समन्ता
I see You as wearing a diadem, wielding a mace, and holding a disc; a mass of brilliance glowing all around, difficult to look at from all sides, possessed of the radiance of the blazing fire and sun, and immeasurable.
The secret of Vishwarupa lies in the above Sloka, wherein Sri Krishna said -यच्चान्यद्द्रष्टुमिच्छसि - whatever else thou desirest to see.
Sri Krishna never said that I am showing the Vishwarupa to you and that these all comprise my Vishwarupa.
He simply said that "See whatever you want to see - यच्चान्यद्द्रष्टुमिच्छसि ".
So whatever Arjuna saw during Viswarupa Sandarsana, it was his own mind's projections and imaginations.
Similarly, attributing different weapons, vehicles to the God, is according to one's own perception.
We hear from the scriptures that the God is All powerful. So does the God need to carry weapons to achieve anything?
Did Sri Krishna go the assembly of Kauravas with weapons?