I have loaded the 100 grain and 110 grain bullets in the .270. Years ago I loaded a low recoil 110 grain for my son. I selected the minimum load for H4831. In some areas the 110-grain Sierra is used on small deer.
But the 90-grain bullet is constructed as a varmint bullet. One of the positive attributes of a good varmint bullet is to break-up on impact. They are normal used on small non-dangerous game. A lot of time they are used on farmland where a ricochet is to be avoided. Ranchers do not care for bouncing bullets around their livestock.
90 GR. SIE HP 90 H4350 .277" 3.200" 58.0 3401 43,700 CUP 62.0C 3603 49,800 CUP
90 GR. SIE HP 90 H414 .277" 3.200" 55.0 3361 42,200 CUP 59.0 3585 50,700 CUP
90 GR. SIE HP 90 H380 .277" 3.200" 53.0 3344 45,600 CUP 56.3 3462 50,900 CUP
90 GR. SIE HP 90 Varget .277" 3.200" 51.0 3409 46,000 CUP 55.0 3596 51,400 CUP
90 GR. SIE HP 90 BL-C(2) .277" 3.200" 49.0 3328 45,400 CUP 52.0 3475 50,100 CUP
90 GR. SIE HP 90 H335 .277" 3.200" 46.0 3313 46,100 CUP 49.0 3459 50,900 CUP
90 GR. SIE HP 90 H4895 .277" 3.200" 50.0 3482 48,100 CUP 53.0 3595 50,400 CUP
90 GR. SIE HP 90 IMR 4350 .277" 3.200" 56.0 3251 41,900 CUP 60.3 3516 50,800 CUP
90 GR. SIE HP 90 IMR 4007 SSC .277" 3.200" 53.0 3293 54,600 PSI 57.5 3508 63,300 PSI
90 GR. SIE HP 90 IMR 4320 .277" 3.200" 48.5 3220 46,800 CUP 52.7 3425 51,500 CUP
90 GR. SIE HP 90 IMR 4064 .277" 3.200" 49.6 3295 44,400 CUP 54.0 3538 50,500 CUP
90 GR. SIE HP 90 IMR 4895 .277" 3.200" 49.0 3268 43,700 CUP 53.3 3507 50,300 CUP
90 GR. SIE HP 90 IMR 3031 .277" 3.200" 46.0 3299 45,000 CUP 50.2 3487 50,600 CUP
90 GR. SIE HP 90 760 .277" 3.200" 55.0 3361 42,200 CUP 59.0 3585 50,700 CUP
100 GR. SPR SP 100 H4350 .277" 3.145" 56.0 3258 44,000 CUP 59.4 3401 50,200 CUP
100 GR. SPR SP 100 H414 .277" 3.145" 53.0 3262 46,000 CUP 56.0 3383 50,700 CUP
100 GR. SPR SP 100 H380 .277" 3.145" 50.0 3160 46,200 CUP 53.7 3274 50,300 CUP
100 GR. SPR SP 100 Varget .277" 3.145" 48.0 3232 44,400 CUP 52.0 3397 50,200 CUP
100 GR. SPR SP 100 BL-C(2) .277" 3.145" 45.0 3144 47,300 CUP 47.3 3243 50,500 CUP
100 GR. SPR SP 100 H335 .277" 3.145" 41.0 3058 45,300 CUP 43.5 3185 50,200 CUP
100 GR. SPR SP 100 H4895 .277" 3.145" 47.0 3298 47,000 CUP 50.0 3401 50,200 CUP
100 GR. SPR SP 100 IMR 4350 .277" 3.145" 54.0 3072 40,100 CUP 59.5 3383 50,200 CUP
100 GR. SPR SP 100 IMR 4007 SSC .277" 3.145" 52.0 3108 52,800 PSI 57.0 3357 64,000 PSI
100 GR. SPR SP 100 IMR 4320 .277" 3.145" 46.2 3066 47,100 CUP 50.0 3220 51,000 CUP
100 GR. SPR SP 100 IMR 4064 .277" 3.145" 48.0 3116 40,800 CUP 52.7 3380 50,100 CUP
100 GR. SPR SP 100 IMR 4895 .277" 3.145" 48.0 3180 47,900 CUP 52.2 3367 51,500 CUP
100 GR. SPR SP 100 IMR 3031 .277" 3.145" 45.5 3139 44,700 CUP 49.0 3339 50,400 CUP
100 GR. SPR SP 100 760 .277" 3.145" 53.0 3262 46,000 CUP 56.0 3383 50,700 CUP
110 GR. HDY HP 110 H4831 .277" 3.250" 58.0 3057 42,600 CUP 62.0C 3214 48,200 CUP
110 GR. HDY HP 110 H4350 .277" 3.250" 54.0 3164 46,900 CUP 57.0 3267 50,100 CUP
I think a 90-grain bullet at a minimum velocity will still be too explosive for you. You are better off selecting a heavier bullet at minimum velocity. A FMJ bullet might suit your needs but is subject to ricochet.
At one time the .270 was my only rifle and I shot a lot of varmints with it. I do not collect coyote skins, I shot them because they are an ugly killer of fawns.