Apparently I’m the only person who pronounces sieve seeve.
Penchant I don’t think I’ve ever heard out loud.
Enthusiast I’m not sure about.
Template I always pronounced TEM-PLATE.
Scythe I have no idea.
Controversial pronounced con-tro-VER-shal.
sieve: siv (rhymes with the verb ‘live’)
penchant: PEN chint.
enthusiast: en THU zee ist
template: TEM plit
scythe: sith (long i)
Siv,
PEN shnt,
en THU zee ust (short u there),
both TEM plet & TEM plate,
sithe (hard th),
con truh VER shul
And what about: Schedule!! = skedjule
I had ‘penchant’ as a Wordmasters word in school (any dopers ever get in on that program while in school?), and according to my “I know everything” teacher it was “pen-chant”.
BTW, try Guadere. 
everton - Yeah, I also checked checked a Penguin dictionary which was published in London, and it lists your pronunciation followed by the “PEN-chent” one, so I assume it is a US-UK division.
Barbarian - Hmm… must be a regional thing, then. I mean, you live in a place where they apparently actually use scythe as a verb. 
Do you also pronounce “lithe” unvoiced?