not sure about availabilty where you live, but i am looking (for my purposes) at this combined "mppt-charger + three-phase invertor"
SOLAX THREE PHASE HYRBID - HIGH VOLTAGE
Battery voltage range [V] 160-800
Max.continuous charge/discharge current [A] 25
https://www.solaxpower.com/three-phase-hybrid/
https://www.solaxpower.com/wp-content/uploads/2021/02/X3-hybrid-G4.pdf
also available in less powerful, single-phase variants:
SOLAX SINGLE PHASE HYBRID - HIGH VOLTAGE
Battery voltage range [V] 85-400
Max.continuous charge/discharge current [A] 20
https://www.solaxpower.com/single-phase-hybrid/
https://www.solaxpower.com/wp-content/uploads/2022/04/X1-hybrid.pdf
from what i found, these communicate with BMS's via CAN/RS485 but also should be able to function without communication, just with the parameters you enter in the settings. So DIY bateries are a go.
posting just in case someone else finds this useful (this post would save me personally a month of my time, if i didnt have to look myself, so, i hope this helps...)