There is WiFi FTP Server from Google Play store which I plan to download and chronicle setup. It has many positive reviews (4.4 stars out of 5 stars) and 500K+ Downloads.
There is a free version with ads and a paid version that is only $0.99 which is a small price to pay to support the developers (IMHO).
My goal is to have static IP address for phone on ...
Tap the "hamburger" icon (☰) to open the sidebar.
Tap the vertical ellipses (⋮) to open the menu.
Tap "Storage Manager".
From here, tap a storage's menu button to edit or delete the server. Additionally, the storage order can be changed by holding and dragging an item.