Hi Maya,
I have done something sort of similar so I can share that and it may help you. This would work really well if you have standard heatmaps that can all use a template with identical settings, but there is no reason you can't adjust things to fit a more complex arrangement.
1) Start with a .geojson file that you want to use to create a template. Bring it into ArcPro using Features to JSON tool. Symbolize the points as heatmap, picking the settings you want (e.g. Radius, Method, render quality). Once done, use Save As Layer File to create the lyrx file you will use as a template.
2) Use python code similar to below (adjust the paths) and paste it into the ArcGIS Pro Python window. This will take your .geojson file, import it into the project's geodatabase, apply symbology from the template, and save the heatmap out to a .lyrx file.
import arcpy
arcpy.mp.ArcGISProject("CURRENT")
geojsonFile = r"C:\Users\christopher.quick\Documents\ArcGIS\Projects\GeoJSON_heatmaps\SportsFields_Points.geojson"
templateFile = r"C:\Users\christopher.quick\Documents\ArcGIS\Projects\GeoJSON_heatmaps\heatmapTemplate.lyrx"
fileName = geojsonFile.split('\\')[-1].split('.')[0]
arcpy.conversion.JSONToFeatures(geojsonFile, arcpy.env.scratchWorkspace+"\{}_fromJSON".format(fileName), "POINT")
arcpy.management.ApplySymbologyFromLayer("{}_fromJSON".format(fileName), templateFile)
arcpy.management.SaveToLayerFile("{}_fromJSON".format(fileName), "Heatmap_{}".format(fileName),"RELATIVE")
3) You'll have to do some testing about moving the .lyrx files around and avoiding broken links. The .lyrx is only pointing to the data so you must also provide the data itself (in your .gdb) if you want the heatmaps to show up nicely for other users.