Light woven glass does not form over square edges. All edges must be radiuses, minimum 1/4". For a planing hull, the transom, at a minimum is returned to square with fairing.
Fumed silica is a bear to sand and is only used where sanding is not needed or a very hard edge is desired. Like a transom edge rebuild to square or fillets between panels where you tape immediately after filleting.
For those woven fabrics, they can be wetted down through the fabric which has been laying on the boat overnite allowing gravity to shape a bit.
The typical next day procedure is to neat coat to fill the weave. A neat coat is mixed epoxy applied at about 2 oz per yard. Use a 1/4" or 6mm nap or less roller. Something about 3-6" wide is nice to work with. The epoxy must not be applied to thick or it'll run. Two neat coats typically fill the weave pretty well, bit for a pristine finish, you may decide to sand high spots and the entire boat and do a third.
A block plane is typically not used for ligjt sanding of wovens, but for humps or drips. I rarely use a chisel or plane and mask when sanding or facing a viral pandemic.
ps-do not use silica in your finish coats; it is not for amateurs to experiment with...I have messed with it and do not enjoy the associated work..you want a hard and smooth surface with the correct mechanical key for paint and will have that with epoxy alone...if you are planning a lot of beaches or oyster beds a bottom alternative is graphite in epoxy..