Have a look at the Dr J series of bass pedals from Joyo. I got the Sparrow DI and think it's excellent. Nice gritty overdrive with the added advantage of a DI pedal. No loss of low end.
http://www.joyoaudio.co.uk/DR.J-Guitar-Effect-Pedals
If you want fuzz or really heavy distortion, try the Little Bear which is a Woolly Mammoth clone. Fantastic, built like a tank and cheap as chips.
https://www.ebay.co.uk/itm/Little-bear-BS1-Wool-pinch-Bass-fuzz-guitar-pedal-Stomp-Box-effects/401469585187?hash=item5d7973b723:g:94oAAOxyrrpTffxM