For the mousse:

Pulse raspberries in a food processor until well pureed. Force puree through a fine-mesh strainer into a bowl to remove seeds (you may have 1 1/3 cups puree), then set aside.
Pour 3 Tbsp water into a small microwave-safe bowl, sprinkle gelatin evenly over water and let rest for about 5 minutes.
Heat gelatin mixture in microwave on high power for about 30 seconds, then remove and whisk for about 1 minute. Let cool for 4 minutes until just warm (do not let it cool completely or it might start to set).
Whip heavy cream in a medium mixing bowl using an electric hand mixer until soft peaks form. Then whip in 1/4 cup of powdered sugar until stiff peaks form.
Use a hand blender to mix cream cheese and 2 cups of powdered sugar in a separate large mixing bowl until mixed. Add vanilla and red food coloring if using, and mix until combined.
Whip the cream cheese mixture on high velocity for about 2 minutes until light and fluffy. Mix in the strained raspberry puree and the lukewarm gelatin/water mixture.
Fold in 1/3 of the whipped cream mixture and then add the remainder, folding until well combined.
Prepare the crust layer, then move it to the refrigerator (do not chill for more than 30 min to prevent it from setting).
For the crust:

Stir together graham cracker crumbs and sugar in a medium mixing bowl. Pour in melted butter and stir until evenly moistened. Divide the mixture into 10 dessert cups and press it lightly into an even layer.
Working in batches, add mousse to a piping bag with a large round tip, then pipe over the crust layer in cups.
Repeat with the remaining mousse, cover cups with plastic wrap, and refrigerate until set, about 3 hours.