Is it permissible to adopt your fatwa regarding intermittent urinary incontinence in the case of involuntary leakage of urine drops a certain time after purification (istinja’) when sneezing, coughing, or moving, knowing that this leakage usually occurs when the area is moist and stops when it dries? And is it permissible to disregard this urine and not repeat istinja’, or wudu’, or change clothes, or prayer, as a facilitation and removal of hardship?

It appears your situation does not fall under the description of "Sahib al-Sals" (one afflicted with continuous discharge). As long as the discharge only occurs immediately after purification (istinja'), you must wait until it ceases, then perform ablution (wudu') and pray, even if you miss the congregational prayer.

Regarding the issue of impurity (najasa), Maliki jurists are of the opinion that it is not obligatory to purify it. However, it is more cautious to take precautions and remove the diaper when intending to perform ablution after the discharge has ceased. The ruling for "Sahib al-Sals" applies if the urine discharge is continuous and its cessation period is irregular.