How to split Garmin Connect Activity in two

[Elksearcher]

A recent Garmin Connect ski activity in two different places needs to be split into two separate activities (fit-file) with the original Garmin logic of not counting positive elevation, positive elevation distance and positive elevation time. If I try this in gotoes and shorten the activities so that I have to separate activities results in Strava not taking into account the original Garmin logic as described. I also wonder if I allow gotoes to copy Garmin Connect activities in Gotoes changes anything?
By the way Strava only allows to split an activity in running or biking and not in any other sport. Even switching momentarily a ski activity in a run activity, split it and afterwards rechange it to ski activity unfortunately doesn't keep that helpful Garmin logic of only counting downhill data. Any ideas what to do best? Should gotoes provide this garmin logic and/or allow splitting of fit-files in the future?
Any help or information is appreciated.