Charging 8 LiIon 18650 cells in parallel
Once you have a number of cells permanently connected in parallel you can treat them as a single cell with larger capacity for both discharge and charge. Separating the cells to charge them is overly complex. 

Design a single Lion charger and BMS (individual cell temp will show faults) that charges your total battery capacity at its best possible rate.

There will be small differences in the cells and the charging (and discharging) current will not be exactly equal across the cells, but the terminal voltage of all cells will be absolutely identical (they are shorted together after all). 
The worst case problem you have is that one cell may fail open circuit forcing the other cells to a higher charge current and potentially resulting in a cascade failure of your pack. If temperature warning is not in your judgement fast enough to provide failure detection, then you could put a Hall Effect current sensor in each battery connection.    

Based on your comment:


  Batteries are in holders(it is cheaper than welding them together). Batteries are in housing and charging one by one cell(outside housing) is not in my interest(since they are below two PCBs)


You should definitely NOT do this. Taking the batteries out of the holder/housing and charging them separately using TP4056 chargers will NOT provide matched terminal voltages from your multiple chargers. You will introduce uncontrolled balancing currents when you plug them back into the holder/housing. The balancing current will certainly not destroy the batteries, but depending on each cells temperature and terminal voltage the circulating currents could be several hundred mA up to several amps.

Putting series fuses in for each cell (as suggested in the comments) is a viable way to protect against a short in one cell (a single cell fire as opposed to an 8 cell fire ...perhaps). You could certainly consider that. 

The TP4056 can't be paralleled easily because the terminal voltage and current thresholds will be different for every charger chip. You might however be able to get away with this in a limited form since the TP4056 is a CC/CV linear charger. I would not suggest you use more than 3 of the simple variety in parallel.   

The 168650 cells vary a lot, here's a typical datasheet.

I would be concerned that if you ever had a fault where only one battery cell is in place, you are seriously overcharging at 3A particularly with no temp sensing in place. However if you are comfortable that your paralleling wiring and connections for the pack are safe enough, then 3A may be a viable charge current for the pack. 

The datasheet for the TP4056 shows that there is a range of output voltages for the CV mode. If your battery pack is depleted to say 3.4V then you can be sure that all three chargers would be in CC mode, so far so good. However they will switch from CC to trickle and CV at different times (voltages), with the highest voltage chip defining the final switch point.



Three chargers would produce 3A, then 2A + 1 Trickle, then 1A + 2 trickle, then 3 trickle as the terminal voltage of the pack rises. Eventually all three chargers would terminate, with the highest voltage chip defining that point.