The facelifted 2020 version of the Kia Picanto swapped the previous four-speed torque converter for a five-speed automated manual gearbox, which we also found to be a poor performer. Unfortunately swapping out this transmission for the older type would be an expensive process. You would need to find a garage willing to carry out the work which may be a challenge in itself, while the cost of a new gearbox would likely be in excess of £1000. Add in the likely labour cost and the whole process could cost you close to £3000.